I believe those are genuine concerns and only highlight the necessity for the BF to publish their own training, alongside better & up-to-date documentation.
To answer your question (“why?”), well obviously to make Blender better. I wouldn’t want Blender to stall just because of these concerns. All this can be relearned, changed. You can also keep your old keymap, I believe that’s an option !
The reasoning behind whomever set this particular hotkey setup is asinine to me. Why ever create a hotkey for a particular “level” when you should be cycling up and down the roster of divisions available?
I appreciate the Alt+1/2 suggestion, its decently in the right direction. But I worry this is a bit of a finger stretch for people unlike myself, whom have smaller hands. Generally speaking, 3D artists, and sculptors of 3D applications have hotkeys that orbit letters closest to (Shift/Ctrl/Alt). - I would hope we are thinking into the future or long-term for Blender to realize we ideally would want to have reflex positioned hotkeys that a user can cycle rapidly “on the fly” without pausing to check their finger placement before doing so, with ease. Also expecting that Blender will perform much better in the near future with high poly meshes to cycle subdivision levels.
As long as we are solely focused and only speaking about “sculpt mode”. Then I beg to question the logic around keeping other “mode” hotkeys in the balance. When they can, and should definitely be over written for the “sculpt mode” itself when active or in use.
I really love this suggestion. For everyone who has stated what hotkeys do what in this thread that are currently in Blender. I had NO idea! - This should remain as a bit of feedback for the dev team.
Right. But we’re at least still calling masks masks I hope? Cause that’s what they’re called in every other app out there, as well as Blender’s other modes. I really think consistency is important, after all it’s one of the reasons this topic exists as well. You’re calling a rotomask ‘mask’, surely you will call masks masks when it comes to texturing and layers, so why we would change that in sculpt mode is beyond me. Also - at one point sculpting may get support for sculpting multiple meshes. Just way too many reasons not to change those very common terms.
I strongly disagree with an inverted mask behavior, but I made that point a couple times already, so I don’t see the point of bringing it up again.
I’m not sure I get the question. I’m sculpting, a face, and want to mask out the eyelids, so I want to switch to a mask brush, paint out those areas and switch back to my previous sculpting tool. I do think it’s essential to have a hotkey for that, yes.
edit.: Never mind, I just remembered that whole inverted mask/calling it selection conversation from last time. 
For what it’s worth, I asked heaps of colleagues at the company as well as previous workplaces, and didn’t find much (any) support for these changes. Blender is Blender though, so you guys do what you think is best.
Ctrl 1-6 keys are relative to viewport levels. So, their goal is just to control display in Object mode.
Generally, they are used to switch between no subdivision to max level of subdivisions.
Adjusting display to have a more responsive viewport or shapes closer to render is another task than editing shapes at different levels.
What I meant is, recent additions, to masking workflow, made the use of mask brush, less recurrent.
For example, eyelids could be masked out using expand tool with symmetry ON.
If you create a persistent face set for eyelids,
_ you can mask them with expand tool + Ctrl Key in an instant.
_ you can hide it to avoid to sculpt it.
_ you can enable auto-masking.
In no way is this a substitute for masking. Creating face sets for quickly painted masks would be a tedium, apart from not having any falloff, and what the expand tool or symmetry has to do with it, I don’t really know.
It might be workflow dependent, but from what I see you can do any of those if you like. Please don’t get rid of something you don’t need just for the sake of it. Look at the most popular sculpting packages - masking is an essential tool used very frequently.
Just making sure were talking about the same thing here -
Create a persistent set every time you want to mask something for a moment? No.
It makes more sense when you consider transferring selections/masks between edit mode and sculpt mode could be added as a feature to blender. If a change makes sense in the context of blender, I don’t think it should be held back because other software is not consistent with it. Blender is blender.
Also personally I would want to try inverted masking first before I make opinions about it, but it does kind of make sense. I’m almost always masking out the area I want, so essentially selecting.
So you’d rather disrupt an established workflow which is used very widely across the industry because you’d like to “try it”, instead of just having let’s say a separate branch to test these sort of things before rolling them out?
Just my 2 cents, but I’m sculpting full time in a high pressure production environment for quite some time now, and I for one am sure that the masking behavior used in literally every other software is the way I prefer it.
Actually, I’d rather not go through this again. From my point of view it’s absurd, and I don’t see any colleagues of mine thinking otherwise. I don’t have to be happy with it, but if others find it cool that’s totally fine.
Yes I meant a separate branch to test it out. I thought you were against the idea based on principle.
I’m never against trying anything out, on the contrary. The more experimenting the better.
Just need to make sure that there’s a solid reason for changing things in the master, and that a wide enough audience is aware of these things. A flexible workflow can sound great on paper, but if hardly anyone is using it in real life it might not be a good enough reason to fiddle with the basics. But ye… try it first, decide later.
To this day Idk how to select bones in weight paint mode while using the Left click select keymap, which is a reason I still use right click select. And to this day, there is still conflict with bone selection and vertex mask or face mask selection in weight paint mode.
I understand that weight+pose mode is a neglected combination, often people don’t know it exists. But super useful nonetheless. It’s just that it’s hard to enter and then stay in that mode, although that’s more out of topic
This is getting off topic guys!
This is not about which workflow is superior. They point that the mask brush is important is clear. No need to deepen that discussion.
The inverted masking workflow in sculpt mode is also not part of this topic at all.
This is about the current and proposed keymap 
It should become consistent with the proposed keymap which keys are used for setting a selection.
But it is not possible right now to select bones or faces/verts at the same time.
Right, sorry about the detour. “masking” became a trigger word for me it seems. 
Circling back to the keymap, I’d second a proposal from the task regarding toggling symmetry. It’d be neat to have a key for that, that’s quite common.
I was just answering according to info, I had.
Eyelids are an anatomical region.
To me, that is making sense to mask/unmask them, several times, during a sculpting work.
Expand tool can be used to create both.
Shift E shortcut is creating a face set. Shift A shortcut is creating a mask.
You can use A pie menu to smooth mask, after creating it with expand tool.
Or you can use a gradient option or texture option to create a falloff, while using the tool.
I just talked about symmetry just because “Eyelids” was written with an S.
Nobody wants to remove masks. The plan is to improve them.
Masks are superior to face sets because they are corresponding to a value, while Face Sets are booleans.
The plan is to avoid to have a trick to store them as vertex groups or arbitrary attributes.
I was just suggesting that, since creation of expand tool and face sets, and because of improvements of gestures tools, the brush is probably less used.
Apparently, a lot of users are not using alternatives to brush, as much as I thought.
I have no problem with the idea of assigning a shortcut to mask brush in default keymap.
I was just asking if people were getting more used to expand tool, now.
@JulienKaspar The keymap should have a shortcut to toggle overlays.
Toggle for Mask overlay is referring to an outdated python path, in both, 3.5 and proposed keymap.
Don’t be mad. I am just asking question.
Should we keep Ctrl M shortcut to toggle mask overlay ? 
I am rarely annoyed by it.
I am more inclined in disabling Face Sets overlay, that is more disturbing with all its colors.
I would like a shortcut for Face Set overlay.
A pie menu for selection operators.
How about the default selection on pressing A and a pie menu on holding A, similar to the way it was made for TAB?
Yea, let’s take advantage of sticky keys. That’s how they’re called right ? using them we can virtually double keymap occupancy
I’m considering to remove the shortcut for the Mask Overlay.
It was added during 2.79 when the overlay system didn’t exist yet and even changing the opacity of the mask was impossible.
Now it’s effortless to toggle all overlays with a shortcut and even add each overlay toggle to its own shortcut or the QF menu.
That could be added to the “Pie Menu on Drag” keymap preference 
But by default I’d leave sticky keys out of the keymap.
Speaking of selection functionality, it is hard to understand the reason for double tab for deselection by default - it is a timing action that was assigned to a basic functionality, and timing actions like double clicks and double taps are known as speed breakers, since they require precise motorics.
It looks like double tap for deselection was supposed to solve a problem that does not exist in workflows that doesnot assume manipulating large scenes (like modeling), but created a constantly jamming selection mechanics instead.
Double tab is not going to be part of the modes affected by this design.
That’s more of a Object, Edit, Pose mode discussion.