I've seen a few posts and comments made by 'tankies' (I had to look up this term, as I've never seen it outside of Lemmy) and I don't think there should be such a moral panic about them. It implies that everyone is so impressionable that they can't be exposed to a minority fringe political opinion without being instantly turned into a rabid and dangerous extremist.
See something you don't agree with? Ignore it. Downvote it. Block it if you really want to. So many people seem to come here just looking for a fight with other users or to get some general outrage out of their system, whether it's 'tankies' or 'anti-tankies'. Just relax. Lemmy is diverse and ever-expanding; there's loads of fun, interesting and positive stuff to see and talk about here.
I will mention that smaller, niche communities have way more harmonious and interesting discussions. This suggests to me that the majority of aggro comes from people who are just logging in and scrolling down the 'front page' for something to do. It's worth putting in a bit of effort to find specific topics you're interested in and then looking at the feed of your subscriptions. It's a much better experience for everyone.