'? It just means it's an environment where they're not at risk of being abused or attacked.'
And this is the problem. How do you do this? Predatory men are drawn to places where there are vulnerable people.
That's why women often prefer, in certain circs, to be with other women. Because they are just way way way safer and vanishingly unlikely to be a sexual predator. And if they are, the victim might stand at least a chance of fighting them off. With men we are much more at risk and if they are dodgy, for most women, there's not much chance of being able to fight them off esp in a circ like a locked cab.
Warboys for example, his victims were turned away and disbelieved for years, because apparently a black cab driver wouldn't do that. He had well over 100 victims.
The idea that sometimes women might prefer other women is sexist and / or transphobic is really prevalent. Even before trans was more in the public eye, there were men trying to shut stuff down that was women only in the grounds of sexism.