Criticizing china can definitely do some good if it's in the correct venue (communists talking to other communists). I'd never hammer it home on reddit (even on the old sub), but as long as it's clear that one is not making criticisms from a liberal point of view, and the discussion isn't taking place in front of a large amount of liberals (e.g. chapo.chat, for now) then it's fair game imo. We can't allow institutions that we consider socialist to operate free of criticism. A big reason that China is worth discussing is to understand what and why they are doing certain things, and what actions a future socialist movement in another part of the world could take.