Example?

Talking about your feelings without fear of a woman getting the ick.

And so what? Given the display of men's feelings w.r.t. to "mixed groups", I (heterosexual male) get the ick about some people here... For me most of it is about the space/relationship where certain things should happen, but I guess scientific misogyny is a thing too.

Why so toxic without understanding (and caring to understand) the other side of the discussion?

Plenty of full explanations in this thread.

candid discussion of relations with the opposite sex without fear of offense

Women probably talk about sex much, much more than men.

Men don't.

Again, completely missing the point.

Cigar smoking.

I know of an older woman (has grandkids) who smokes cigars at the cigar shop I smoke at. The discussions with "The Boys" are different when she's around.

I'll have to let my HR manager know women can't smoke cigars. She clearly doesn't know, went through a bunch at our last company meeting.

There are no women only spaces where I live. Nor were and no one complained. Unless you talk about monastery of toilette.