Because they're a reactionary group formed in direct opposition to feminism

Consider the following: Opposition to feminism is tantamount to opposition of the the National Organization of Women's long and sordid history of opposing joint default custody of children in the event of divorce, which they've rallied against basically everywhere, everytime it's been proposed. That's not even getting into the fact that giving custody to the mother by default, supposedly based on "Patriarchal" ideas of gender roles, was actually the work of the Tender Years Doctrine, as advanced by feminists such as Caroline Norton, and as such was acknowledged as one of the earliest feminist victories right up until all gender inequality had to be shoehorned into Patriarchy theory. The fact stands that the most prominent feminist organization in the US has been the most staunch opponent to gender equality in that arena, and there's no way to deny that fact.

Opposition to feminism is tantamount to opposition of organizations like NOMAS, a feminist organization with CADV affiliation, who explicitly deny that men can be the victims of domestic abuse at the hands of women on the basis of "they're so much bigger and stronger" on their official website. And feminist initiatives like the Duluth Model, which tacitly assert the same thing in their teaching that domestic violence is exclusively the manifestation of toxic masculinity as a means to control women, and thus leaves no recourse for men who are victimized by women. Or, for that matter, lesbian women who are victimized by other women. The fact stands that our most reputable feminist organizations have been staunch opponents of gender equality in that arena, and there's no way to deny that fact.

Opposition to feminism is tantamount to opposition of noted academic Mary Koss's gynocentric definition of rape as something that must be penetrative, thus barring the possibility that a woman forcing unwanted sex on a man can be considered "rape"; or the CDC's adoption of that standard while she was employed there, so that female-on-male rape is still relegated to the lesser category of "sexual assault" to this day. The fact stands that this is the direct result of the actions of one of the most influential feminists in living memory, and you barely, barely deny that fact through semantics.

These aren't "tumblr crazies", these aren't lone writers on Jezebel, these aren't wackos with wordpress accounts defiling you ideology. They are in all ways synonymous with 3rd wave feminism, controlling funding and directing policy from positions of authority, while "good feminists who really care about equality" blithely ignore their actions and legitimize them with the lip-service they play to equality on their blogs.

Yes, the MRA was formed in opposition to feminism, just as women's suffragettes were formed in opposition to people denying women the right to vote, and for the exact same reason. Because feminism is the problem. Feminism is a massive problem, and very nearly the entire problem, and no amount of petty rationalization will get around that very basic fact. And if it sometimes "espouses hateful speech", I don't see you people falling over yourselves to distance your movement from Solanas and Dworkin. You have to blow off steam where you can, and God knows it's gonna take me five, six edgy jokes on the edgy joke subreddits to blow off the steam I'm keeping in check right now.

I'll have fun with that; hope you do too.