Pretty much this. I see a lot of arguments that their support of russia is "critical support" but there's no criticism of it in their discussions. Being against the western imperialism, it seems, automatically grants a country a title of "lesser evil" and everything it does gets conveniently glossed over.

That said, I can't in good faith assert that everyone or even majority of the users on so-called "tankie triad" instances are tankies. It's more that the tankies have a loud presence there that isn't moderated. Most of the people from hexbear and .ml I've interacted with have been polite and rational in explaining their worldview.