lemmy.ml is federated with lemmygrad.ml, and both are old instances (also run by the same people but that's less relevant here). Point being is that all the people on tankie central are subscribed to !worldnews@lemmy.ml for their worldnews community and thus you get a certain voting pattern you don't see in other worldnews communities even if you don't see any lemmygrad.ml users commenting.
For values of "public info" that involve running an instance and inspecting the database. Also lemmy.ml itself has quite a high proportion of tankies as it's the instance that tankies tend to use to interact with instances defederating lemmygrad.ml.
This only further proves the point that up/down votes are useless here. I can have an account on each federated instance (just one, so not to possibly run afoul any local server rules) and have a script to just run through all of them to downvote something. Could easily be a hundred votes at my singular whim.
If the names of the accounts are not particularly linked... you wouldn't really be able to tell that there was much vote manipulation either.
When smiles and frowns can be manipulated via bots
... I'll agree... but until then, especially on instances that believe communism works, they're beyond useless. Hell many instances disable downvotes so those people can't downvote anyway.