@ThinkingPolygons If you look at the task (linked above the video) it mentions the reasoning behind this. Selection, activation, mode toggle, etc. are all mixed up, and we are separating them. So yes, currently you can click the camera data icon to change active camera, but in my branch you will not be able to.
@giuseppebufalo fixing that is actually in my plans for next week. I linked to the task above. Also, if you have other feedback, post it here: GSoC 2020: Outliner Discussion and Suggestions