How poorly have you been educated, my friend? That's nobody's theory - it's verifiable fact. And discussion of that didn't just start in the 1970s. Ever hear of women's suffrage, or coverture, the English common law practice (also used in other places, including the US) where married women had no legal status at all? They could not own property, and essentially were "covered" under their husband as a type of social child. Money that she inherited or otherwise brought to the marriage was now his; the children - his; if he wanted to beat her, he had the legal right to do so (and at some periods in time this was actually encouraged by the church to keep women in line). Good lord, man, I don't have time for a 25 minute history lesson.
Women were second class citizens by law in the US until about 50 years ago. I'm not familiar with the UK laws as relates to this but given that there are many social similarities, I wouldn't be surprised if it were similar. There were literally hundreds of laws that applied to women that did not apply to men and hundreds of rights that men had that women did not. 50 YEARS AGO! How exactly are women going to maintain power that they don't remotely begin to have? It's a nonsensical and irrational idea. It's so out of line with observable, verifiable reality as to be ludicrous.
And you might as well ask how white people have allowed brown people to gain so much power and rights. It's again a shocking lack of understanding of the world, of what happens in the news everyday, of basic entry level sociology. This shit has been fought for tooth and nail, often over decades of time, and at great cost. Women's suffrage took nearly one hundred years. Rich, white, Christian man haven't really allowed for much - it's been demanded of them and had it taken from them for the most part. And, the fight continues. The more gains those "others" make, the more people traditionally higher to the apex of the pyramid of power freak out. It explains Brexit, it explains Donald Trump. They are doubling down, trying to keep people "in their place" in the traditional hierarchy of power and when they see that they can't they ramp up the domination and the attempts to control.
The fact that J.K. Rowling and her pals don't have a good sociological grasp on what they are doing and what their motivations are is too long and involved to go into in this format. Just suffice it to say that patriarchy is violently opposed to anything that transcends the gender binary and it's about the stupidest thing in the world to pretend trans rights are a patriarchal ploy of some sort. I get that they say that bc they see it as "men" pushing into women's spaces, but that's also stupid, reductionist, reactionary bullshit.
For the foreseeable past, all science, and all institutional constructs were white, male centric. Everything was viewed through a patriarchal lens - often to horribly off base or discriminatory result. There are innumerable ways that has led to shoddy science and structural oppression and marginalization - so many that I can't even begin to list them here because it could fill a book. But, for a short version, read this story.
Moving away from that is not dismantling the "correct" or "normal" way of doing things. It's balancing out demonstrably faulty and problematic structural dynamics with a more realistic perspective. Feminism isn't forcing baseless notions on the world (again, review your history and learn some sociology) but dismantling old problematic and sometimes quite stupid presuppositions that came out of that sort of thinking - and it's being adopted by more people, because a lot of it is demonstrably correct, and more fair when you move away from a narrow androcentric lens.
An example of this is the research and structuring of guidelines by the APA for working with men and boys. Feminists didn't get to them - rational thinking got to them after spending 13 years reviewing research done primarily by men. It was patently obvious that a small box of acceptable masculinity based in aggression, and artificially suppressing normal human emotions is going to be bad - for men and for everyone else. It's not exactly rocket science to see that once you step back from the norms that have preached this as vital to being "a real man."
The social system of patriarchy influences absolutely every single aspect of our culture(s) and is at the root of every single one of our social problems. I say that as a social scientist who has been studying this for over 20 years. Homelessness, police brutality, racism, school bullying, etc. - those are all reflections of living in a patriarchal dominance hierarchy system.
Read the story I linked you on a domination culture. It doesn't use the term patriarchy even once. And, I don’t think there is any point in continuing. You seem to have an absurdly naive view of the world divorced from verifiable history, as well as the news of today and it skews all possibility of actual dialogue.