I think there’s a mixture of things here.
First, if an ATHLETIC competition, it makes all the sense in the world to separate genders. As much as equality is a good legal and cultural principle, we shouldn’t be blind to the fact that men are just bigger, stronger, and faster. I saw a fight between one of the best MMA female fighters in the world and an average-ish local MMA fighter for his region who was male. The man kicked the woman’s ass. This guy wasn’t bigger. They were in a similar weight class. But he had longer arms and more power per pound.
Skill matters. But there are undeniable realities that nature creates. That female MMA fighter would probably clean my clock…but unless the skill gap is ENORMOUS (as it would me between untrained and out of shape me and this female MMA), women just can’t expect to compete with men in physical competitions.
BTW, Serena Williams has said this also. She’s the most dominant female tennis player of all time, and she was asked where should would rank on the men’s side. The reporter clearly expected her to confidently brag that she would rank highly. I forget her exact answer but she herself said she wouldn’t be among the top 200 or something like that. It was a very sobering analysis. People make a big deal out of Riggs vs King, but Riggs was old and out of shape by that match.
Now – Chess is NOT an athletic event. I would argue that a sport requires some athletic component, and that chess is a GAME, not a SPORT…but that’s irrelevant. Chess has no athletic component. I suspect that a woman who dedicated herself to the sport equally to a man would do quite well. I have no idea HOW well, or how the differences between male and female brains would factor in. There ARE differences. That’s a neuroscience fact. But individuals have large differences also, and I won’t presume to know which factor would dominate the other.
The existence of women’s only chess groups likely represents that historically women are underrepresented in chess and so a women’s only league might make them feel more at ease and increase it’s perceived accessibility, which is good. If a woman WANTS to compete with the guys, she can, which is also good.
Queen’s Gambit was a fun show, but in reality a little girl finding herself competing only against the guys might feel out of place or intimidated and decide not to participate. Whereas with a group where she gets to play other girls she might feel more comfortable and stick with it, fall in love with it, and she’ll go as far as her intellect and hard work take her.
However, these women’s only chess groups might ALSO be a holdover of a long held and only recently rejected view that women are intellectually inferior to men. It was a mainstream view for a LONG time. And so these groups might have been set up for very condescending reasons. But again…if it improves accessibility…is it a problem? I feel like we can acknowledge the bad reason and look past it.