I've been told that women are socialized not to overtly disagree with or otherwise oppose men.

Avoiding overt disagreements is solid advice for anyone who wants to be well-liked, because they are often a social cost to the disagreer, and primarily benefit the person they're disagreeing with.

It's not clear to me that the advice to not overtly disagree with men is as specific as it sounds, since it seems like overt female-female disagreements are also discouraged. To the extent that it is specific, I do suspect it is due to the physical risks involved.