The key error made by people in your position, and I know this because it used to be my position, is thinking that the foggy soup of tropes and cliches pounded into us from birth by western media in any way approaches a scientific or unbiased assessment of an entirely different way of organizing society and human life than the one whose propaganda we grew up immersed in (and whose existence has caused a mass extinction event).

Hating two things is not the same as putting them at the same level

True at the most basic level in the same vein of saying 2 things can be bad. Yes it is possible for 2 things to be bad but no one who ever says this ever means it in that way it is nothing but thought terminating cliche if not expanded upon. The same is true here leaving out the other major ideological power of the time leads the framing to the implication that it sits above the other 2 evils (who are then equatable in comparison).

and I mean to do no such thing

Even if you didn't mean to the way you chose to frame your comment clearly implies some level of equation between the soviet nondescript horrific crimes and the Nazis in comparison the the capitalist powers who are absent from your comment.

I don’t think you would claim that hating a lesser evil in addition to a grater evil is an example of trivialisation.

Again on a base level this is true but in the framing of your comment there is clearly a level of equation (even if unintentional).

What would make you hate a force for decolonization and workers' rights?