The nameplates don't have to take up more space with this feature because implementing this can be as simple as adding the blue or green icon overlapping the frame of the nameplate.

Pls not... the NamePlates are big enough...

Is this really an issue that you need a Feature for? all you have to do to see if someones on pc or quest is to tap the Menu and see if they have blue or green dot next to their name, this just seems more of a lazy thing really, you cant be asked to hit/tap a button and see witch color the dot is really? Its that hard and to much work for you to do? and why dose it always have to be displayed for? I see people using it as branding more then anything, and people on quest get flank for not owning/using a PC when they are found to be a Quest user, so having it on all the time would be more an issue, not to also point out that it would take more room and GPU to display, sure maybe small but it adds up as a whole.

Or just having different shapes of name tag. That will help to identify without making a mess on the screen.

Why, how and who does this benefit? more visual clutter for no reason.

Personally I think having this as an option would be nice, but not a permanent setting.