I’ve recently tried to use peertube and I think it could improve a lot if it showed all the content in all instances. But instead you have to look around many instances to try and find something you like. Then there’s other thing, it can’t suggest content if it doesn’t know what you like and without sharing the data between the instances it doesn’t know anything about anyone. If the user data was encrypted and shared between all sites, when you log in it could use the now decrypted user data to suggest content. Or maybe it can share the data with third parties, I don’t really know.
To find videos across several instances there is this (as official as it gets) search engine: https://sepiasearch.org/
In my opinion it would be better to have a main peertube that displayed the most relevant videos from all instances and implemented that sepiasearch. And leave the details about how to create instances and the fact there are 861 PeerTube websites on another tab instead of the main page where it’s just confusing people.