They want to make abortion illegal, a major point of most GOP platforms. So I guess they do believe they have the authority to have a certain amount of control of women's bodies. Certainly it is also a simple view to assume just because something is legal, there is no aspect of control. Funding, access, privacy, there are tons things to consider outside of just if it is legal.
I never said GOP = patriarchy. Just that there is a "systematic, coordinated campaign against women's reproductive rights" and that certainly isn't a fringe statement. This campaign is indicative of one of the OP's definitions: "interwoven social structures that promulgate certain ideologies, doctrines, and social customs."