This doesn't address everything in your post, but something to maybe keep in mind: I've found men to be much less forthcoming about their struggles in school, especially in a competitive grad school environment. Additionally, men, like myself, have been systematically "affirmed" by society of their ability to perform in STEM programs, which gives many a confidence that is often misplaced. This is just to say that when you are taking the "temperature" of your classmates, the observed states of men are probably less informative of the hidden states than they are for other students(excuse the hidden markov model terminology).
Edit: As an aside, covid-19 is definitely exacerbating inequity in academia. I have also found, like most others, I struggle much more in online math and statistics classes than in in-person ones. I hope you can stick it out until things return to a more "normal" situation.