If you think about the chain of events, it makes sense. While there were people using lemmy pre-exodus, the giant leap in userbase is a direct result of the exodus of users from reddit.
So it stands to reason, as that core group of people interacts with each other, and is then exposed to further shitty behaviour from reddit CEO… considering they were unhappy enough with reddit to move in the first place, it’s no surprise that exposure to more and more shitty behaviour leads to that feeling hardening.