I read their comment too, no need to worry. Anticommunist instances like Lemmy.world and, relevantly Lemmy.ca, still can’t get rid of Communists even by defederating from Communist instances.
Assuming that whole instances are anti-anything is a great way to judge a whole swath of people quickly and look childish, it’s less useful to do anything else.
My point is more that Lemmy itself is structured along Communist principles, while Reddit remains the right-wing Lemmy. Choosing Lemmy over Reddit is ideological in nature, which means there is going to be a steady influx of Communists and other Leftists, less so Liberals.
No, Lemmy is just decentralized in nature, while that’s attractive to fringe left groups like hardcore communists, it’s also attractive to anarchists and fringe right groups like hardcore libertarians.