A common understanding of the male gender role has invalidation built into it because men are prized for their stoicism and abhored for their weakness. Many men are unhappy with the role but don't have safe opportunities to escape it, so they choose to level the playing field by invalidating all women in proportion to how invalidated they feel. Then many of the women who've had to deal with men like that (or men who are abusive for intrinsic reasons) turn around and throw the medicine back out at all men, which is just as understandable. It's another one of those self-reinforcing cycles.

I also consider myself to be an MRA and I suspect there are a surprising number of us here who have experienced or been forced to recognize the ways in which men are uniquely not lucky in society. It's like living in a different reality. A lot of disagreements on the internet and in real life seem to me like people from different realities trying and failing to communicate with each other. If the difference in basic assumptions and life experiences is too stark, no amount of discussion can bridge the gap.

I don't know exactly where I intended to go with this comment, but I felt I should respond since I had a similar gut reaction to that part of the OP.