Most do realise this. Most are oriented this way.
I do know most people are aware of this tactic. But I feel I also encounter people who are similar to ultras in the sense that they defy everyone, be it the US, China, Russia or whatever, but end up inadvertently (I think) focusing their attacks on opponents of the US, be they communists or not.
I think I know a lib when I see one. I am referring to people who say "Fuck the CCP, fuck the US" and truly believe in what they are saying, and then end up online attacking mostly the former out of some gullible principle.
Maybe you're right and the people I'm describing don't exist, or are so few in number as to be irrelevant. But a lib makes more sense to me than these people.
The moral imperative of these people is always supporting NATO hegemony as global peacekeepers, so fuck other countries' interests and alliances.