Honorable mention: @indivisibleteam - no full eXit yet, but dramatically reducing usage of their 260K follower account and removing it from their website and emails. Their post explaining the reasoning is worth a full read:
I concur, of course, especially with this:
"When trusted voices begin to leave the platform en-masse, X will lose its appeal, its pull as a source of real-time information, and its remaining legitimacy with policymakers and regular users."