But now you've also influxed a tonne of women into that workforce, meaning now you'll need to hire disproportionately more men next generation.
Even though we reached equal representation? You want to reinject more of one side to recreate the imbalance we were getting away from a minute ago? The only gap is between generations, when the old people retire, at first that'll be a lot of men since they're the only ones that were there, but it shouldn't be that hard to map that out to maintain equality through the change. Plus, hiring seniors is a thing, so hiring older women and not all young women can immediately balance that retirement sausage fest faster, removing the gender imbalance per generation. You're supposed to hire at all levels, entry level only is just more corporate speak. And that's not just about women or minorities, that's already a subject for people who can't get a job because companies want both experience and entry level pay, this isn't new, it already hits everyone, including poor white men. Fixing this helps everyone.
Also, I mentioned it before, but I'm not talking about a single company on a single job position. As long as everyone plays the game, and not everyone has the same amount of people on the same generation and retiring at the same time, it shouldn't be that hard to smooth out the curb to the middle, and then stay there. All HR departments in the world should know how to plan that, they're built around their love of Excel sheets.
Hiring 50/50 is of course part of it, yes, it's not like the whole world is really doing 100% women only everywhere, you know that's just not reality. If one company is doing "men need not apply", you know there are other companies that aren't. Of course that depends on the job, because places that say "this job is only good for women" (like, you know, low-level healthcare), or the other way around (mechanics? That's only for men!), has been an issue long before people started complaining about diversity hire, they just didn't like to mention it because they liked it. Hiring exclusively women was fine when it was for low level jobs that men obviously don't want to do - except there's plenty of men who do want to work in healthcare or childcare or education, and they can't.
Encouraging young men and women to branch out more is of course a good idea, but we've seen for decades that women who want to try STEM and the likes often ended up chased away by men who say "it's no place for women" (students, senior employees, teachers) and because the culture is already plagued by sexism and racism and exclusion and actual threats. Starting at the bottom and doing nothing else doesn't actually work, we've tried that and it failed hard and we've all gone surprised pikachu face about it. The fact is that young women do want to try STEM, until they get assaulted and victimized, just like there are young men who do want to try traditionally female jobs, until they get mocked and harassed for not being manly enough. These people already exist, we're already telling them to try it out - only to destroy them within a couple years. We do have to include the middle and the top right from the start, it has to happen everywhere, and people who fight back have to be forced to accept it - we have to clean up the "locker room" culture and the "traditional gender role" culture to protect the people that want to join these places.