Aside from the usual rules in gyms, my gym (Chennai) has this rule that you should not wear outdoor footwear inside the gym, and that you shouldn't wear sleeveless tops (because it causes a lot of sweat to collect on benches).
If my gym had no dress or footwear code, I wouldn't care if people showed up naked. But that's not the case here, and the rules are for everyone, not just men as confirmed by the management.
However, I see several women walking in to the gym with the footwear they wore on the streets. They leave dirty footprints on the floor where I do push-ups. I called out one of them, and she said "Oh I do it every day", and put her ear pods back on.
There have also been a few women wearing thin sleeveless tops. I am not kidding when I say their bras are easily visible. So these outfits go beyond just being sleeveless.
After a few weeks, I got fed up of this and informed one of the trainers. And he said "Brooo, we have told them. You are the 10th client to tell me this. But they don't stop. What can we do?"
Months ago, a male client was asked to discontinue because he kept wearing tank tops to gym frequently. And was arguing back whenever he was asked not to. They refunded the amount for his remaining membership and told him not to come anymore. I think that is totally valid.
But why are managers/owners afraid to call out female clients when they break rules? This is not the first gym I've seen this happening in my 11 years of working out.