As the title says, I believe that if the BF was to focus on performance for edit-mode and OpenSubDiv for 2.93 (instead of adding new features to those areas), the net benefit for users over the next year. especially for LTS users, will be far higher than if new tools and tool options were created instead.
We have enough tools for now, but we can’t use them to the fullest if we can’t work with a huge number of polygons. We also can’t take full advantage of rigging tools if it is not possible to have subsurf active during animation. Also think of the people working on your new open movie, do you think they would benefit greatly if performance was a bit better and they did not have to resort to workarounds (like cutting objects into little pieces)? The bottlenecks are known, now help us have access to a Blender that can plow through scene creation at 60 frames a second.
Please get this done, as it is one of the few major sticking points left in the whole application.