Maybe. That depends entirely on the extent to which Musk can keep it together -- past Mastodon growth spurts correlate with his erratic and sometimes unhinged policy changes and outbursts. But I don't know what will make comedians and polticos move out; I suspect it'll be individuals coming over to Mastodon here and there and then suddenly it'll reach critical mass.

Disagree about Mastodon -- I think it or the protocols backing it, will be the glue that holds the rest of social media together. You may not be using something branded "Mastodon" in 2035, but it will probably be Mastodon underneath.