Regarding lemmy.ml: yes, you should avoid it. It does not make sense to create politically-neutral communities on a politically-oriented instance.
Regarding Dessalines: The great thing about Lemmy is that I don't need to give a shit about the lead developer's politics, because he's not in control of how Lemmy is used, and if he ever tried some kind of heinous cross-instance power grab, it would get shut down before it got started.
Regarding the cognitive dissonance required to A) value decentralization of power, and also B) support the CCP: 🤦