A lot of left-wing political theory and analysis just consists of pointing at objectively good things and then pathologizing them as evil and bigoted. So, if you ignore their stupid conclusions and whining, then a lot of their observations can be helpful.
Take critical race theory, for example: Western Civilization was objectively founded to benefit White people at the disadvantage of everyone else, and that's a good thing. White societies are irreparably "racist," and that's a good thing. Defending the West and the values of the West is defacto defending the political power and ideological values of White people, and that's a good thing.
The problems with Leftist theory is not their observational analysis, but their genius solutions to the "problems" (basic facts of nature) that they identify (pathologize).