The centralized platforms seem doomed to reach a point where they’re squeezing as much cash out of users as they can while users provide their content for free. If we need to create multiple accounts to fight back against enshittification, I think that’s a fairly minor downside for increased competition.
Creating and managing multiple accounts is also shitty, if not enshittification. If people have to choose between shitty-hard and shitty-easy, they're going to choose shitty-easy or just opt out entirely.
Twitter is just text messages as spectator sport, people can do without it. The real problem is a narrowing range of media in general through active state action, continued consolidation, and the fact that tech multibillionaires just buy outlets like twitter, The Atlantic, the WaPo etc. and use them for egotistical social manipulation instead of to inform and stimulate important discussion. If it weren't for that, twitter would be the celebrity bore that it always was before weird twitter took the piss out of it. Now it's serving as an outlet for every frustration because those frustrations have been censored out of traditional media.