I’ve checked a few instances of federated YouTube alternatives and just… no. Most of the content is right wing guys looking for a place to spread hate they can’t elsewhere. The type of people that watch Andrew Tate and Admin Ross. Lemmy is Great though, mastodon seems a little boring compared to twitter. The fix to that would be Elon fucking up enough that the very change averse average internet user would be willing to try mastodon.
I’m fine with threads federating with mastodon as it means more content which means people won’t immediately dismiss mastodon because it’s too boring for them, but I don’t want Lemmy to federate with Lemmy any more than I want to read tweets on reddit. They’re different types of platforms for different things.