I would love to see this. Zoom needs to implement this if they want to be used by the streaming community. Nothing more frustrating than composing your OBS screen to a Zoom window and have the window accidentally get resized. Not to mention always having to make sure the participants you want to focus on in OBS are in the same positions in Zoom. Spotlighting is a click nightmare. What a pain!
This is why I recommend Skype until Zoom gives us this feature.