Well running a server and no longer interacting with a service can be two different things. From an organizational standpoint I could absolutely understand them not wanting or needing the expense of another service to maintain. Even for just their own use. As long as they still have accounts and post to the fediverse. I don’t see a big issue
A few things. Communism isn’t Marxist leninism. Communism isn’t authoritarian. And it’s not just Stalin and Mao. It’s literally everywhere Marxist leninism has ever been attempted. Communism is a classless stateless society. Therefore a Marxist leninist government will never become communist. Because they are defined by their class separation of those with political power and those without, and the strong overbearing presence of the state.
There’s nothing objectionable to Communism whatsoever. And no one should have any qualms about defending it ever. What we should question is why one group of authoritarians the Marxist leninist desire to be so closely tied to it. And another group of authoritarians the capitalists demand everyone be afraid of it.