Shaming people who leave a toxic place because the new place is not 100% non-toxic is a weird flex that happens on Twitter right now.
Sure Twitter alternatives are not the most accessible, but neither was Twitter when you joined it (unless you joined in the last 12 months or so). Pretending Twitter didn’t become accessible because people joined it in the inaccessible state and lobbied hard for it to become better is not recognizing Twitter’s history in this area.
Yes, Mastodon is not super accessible, and there are barriers. But there are good and well-documented workarounds (like there were on Twitter back in the day!) which we can build upon. Because nothing is won when Twitter is defunct and there is no alternative. We have to start now.