I think the fairest way to go about solving this problem is to abolish gender-based divisions altogether and just have tiered divisions based on athleteles' actual performance... A Division, B Division, etc.
It wouldn't knock down women's sports, it would eliminate it. It would also eliminate men's sports too. We'd just have sports, and the only emphasis would be on individual achievement. Which is really the fairest way to go about it... having separate divisions for men and women is tantamount to having separate divisions for black and white.
If sex is a factor for performance, then people will just naturally fall where they need to with performance-based divisions, without unnecessarily limiting anyone who is perhaps above average for their sex. And if sex isn't a performance factor, then there's no need to pretend like they can't compete with one another with different divisions for the sexes.
I just want to comment on this. If someone actually ever tried to go this route 99% of sports would be Men only. Dominated only by men. That's not an exaggeration and not a knock on women, just reality. I actually prefer to watch some women sports to men sports like hockey, volleyball, and ping pong, but they couldn't compete. At all.
From olympic sports I can just think of Gymnastics and synchronized swimming where women could compete in their specific events. Think about sports like soccer, basketball, volleyball, etc. No chance for women. Diana Taurasi couldn't even make the cut in the D League. Carli Lloyd couldn't make the cut in the USL III. And I really like both of those ladies' games.
If you think of major contact sports like MMA, boxing, Rugby, Olympic Wrestling, etc there's even less of a chance that women are anywhere even in the middle divisions as per your idea. Gender needs to separate in sports for obvious reason, same as weight for certain sports. The reason some girls can compete with guys in HS wrestling, for example, is because boys are not yet fully developed. A 135lb man is significantly different than a 135lb boy. And one of my favorite wrestlers ever is a female (Maroulis).
Would that be fair? Sure if you want men to dominate all sports, probably the top 10 tiers or whatever.
Long distance swimming is the only athletics based sport where women are even remotely competitive with men. I love women's sports, but let's not pretend that the performance is similar.
Even that is not really that competitive when you talk about World championships events. This is the winning and last place from the last worlds.
5K
M - Winning: 54:31.4, 61st: 1:06:01.6
W - Winning: 59:07, 57th: 1:11:55.7
49 Men faster than the winning gold for women's. All over 1 minute faster
10K
M - Winning: 1:51:58.5, 65th: 2:15:41.2
W - Winning: 2:00:13.7, 57th: 2:28:21.8
51 Men faster than the winning gold medal for women's
25K
M - Winning: 5:02:46.4, 25th: 5:49:57.5
W - Winning: 5:21:58.4, 19th: 6:05:20.0
21 Men faster than the winning gold medal for women's