From u/mradiscus:

The problem with 'patriarchy' as a concept is that it is completely ambiguous. And in my opinion, purposefully so. Let me explain: I think we all agree that we don't live in a society in which fathers hold total authority over their wives and children. In fact, the marginalization of fathers is one of the most pressing issues of the MRM.

So obviously, this is not what is meant by patriarchy. But what is? Here's my take on this: The expression 'patriarchy' - as wielded by your run-of-the-mill feminist - is used to invoke a certain meme: that men have all the power, that the totality of women are oppressed by the totality of men, that - as you define it yourself in this thread - masculinity is valued over femininity, and so forth. All these sentiments are either demonstrably false or purposefully misleading.

Now, when the concept comes under heavy attack, feminists retreat to their motte: all of a sudden, patriarchy means nothing else and nothing more than the existence of restricting gender roles (you can't just call it that, of course, because then you would forgo all these neat little associations I spoke about). Nevermind that a whole lot of these restrictions are actively upheld by feminists: they reinforce them every time they deny a woman's responsibility for her own actions, every time they belittle and shame men for talking bout their plights, every time they use their hateful shaming tactics.

Feminists pretending 'to fight the patriarchy for the benefit of men', it is nothing but lip service. Nothing illustrates this better than their insistence on the concept of patriarchy. They hang on to it because it justifies both their lobbying for rules and institutions that actively disadvantage men and their continued demonization of everything male. After all, it's them who have all the power and are overvalued, right?