Femenism benefits men too. I am a man and while I primarily support feminist causes for women themselves, there's no denying that patriarchy also damages my life as a man. All these toxic behavioral "rules", the machoism, the competitiveness, the hiding of emotions.
That is the irony, a lot of incels and other misogynistic young men are suffering from that which they are siding with, and are fighting against what could ultimately help them.