Excellent analysis. Although we may have a couple posters not extreme conspiracy theorists who still oppose anything Biden does, even if it falls in the “stopped clock right twice a day” category.
I might also propose a couple more groups.
5th group: People who are start off as isolationists and don’t much like anything the US does outside of its own borders, while Russia should be allowed to run rampant. This morphs into sympathy for Russia and inability to see the bigger pictures of both current events and history, as well in some cases expression of actual approval of harm to the US / US allies, or approval or rationalization of actions of bad actors such as North Korea, etc.
6th: Those who genuinely think / feel Russia should be allowed to run amok so Pooty doesn’t act on his nuclear threats — never mind that such a course guarantees huge nuclear proliferation by just about anybody capable, and that is in turn in the long run a practically guaranteed Armageddon.
Feel free to refine the above or add sarcasm - it’s dashed off rather quickly!
I will say this in response. Your fifth group is real, but I think it would fall within my first group. Blind hatred of Biden.
Your sixth group is understandable, but I think these people largely fall into the pox upon both houses crowd. I don’t think many actually cheer for a Russian victory, although perhaps some do as you say, as the bitter pill to swallow to save the entire body.
Se my comment #184 for another more dangerous explanation for pro Putin/Russia comments here.