What can universities do? Well, that’s easier. Stop hiring white cis men (except as needed to get/retain people who are not white cis men) until the problem goes away. If you think this is a bad or un-serious idea, your sexism/racism/transphobia is showing.
It is worth considering your complaints. Are you worried it’s unfair to men? Are you concerned the quality if your institution would plummet? Are you worried about all the brilliant minds you’d be missing? List your reasons and ask yourself which ones you’d value over your own freedom. Women are not free, and even our allies tend to only want us equal-ish. As long as we get there on their terms, as long as they lose nothing.
If you are on a hiring committee, and you are looking at applicants and you see a stellar white male applicant, think long and hard about whether your department needs another white man. You are not hiring a researching robot who will output papers from a dark closet. You are hiring an educator, a role model, a spokesperson, an advisor, a committee person. When you hire a non-marginalized person, you are not just supporting this one applicant whom you like, you are rewarding a person who has been rewarded his whole life. You are justifying the system that makes his application look so good. You are not innocent. You are perpetuating a system that requires your participation if not your consent. When your female students of color have no role models in your department, that’s not “meritocracy”; that’s on you. Again, if you think the “great mathematicians” are disproportionately male because of meritocracy, then your sexism is showing.