Lemmy.ml is one of the big communist instances, sure, but in no way fascist nor fascist collaborators. Communists support collectivization of production and distribution via establishing socialism, economies where public ownership is the principle aspect of the economy and the working classes are in control of the state. Fascism is about cementing capitalism and bourgeois rule in countries where capitalism has decayed. These stand diametrically opposed.

On Lemmy.ml's meme communities, you see lots of leftist memes. Fascists are banned, as well as fascist memes.