The real question is: What is happening right now?
The $3500 dollar AVP has just created an entirely new interface for people to interact with computers. There are developers that are working as I type this to get first mover advantage on a new surface that could be as influential as the shift to mobile. Numbers are low now (I read 10,000 subscribers from... the Verge I think?), but that's now, when we're debating the usability of the entire platform.
What is the app that will make you buy Apple Vision Pro 3 in 2 years?