I think it's ok to approach women, but it has to be fast, and polite. "Excuse me, I was wondering if you would be interested in having a coffee together, you seem to be someone nice and fun to be around" (this only applies if she is with friends/laughing, etc..) then you slide a piece of paper with your number/IG. "Have a nice day" and you disappear. Unless she is a radical feminist, she would be ok with being interrupted for 2 minutes.