Oddly, it was just a couple of days ago that I was prompted by Lenore Skenazy's Persuasion essay about "free-range" children to make a comment similar to the following:

I agree with the author's suspicion that the flirting baby has been thrown out with the harassment bathwater, and that relations between the sexes would do well to return to something less fraught. It's important that people understand, though, that there's no perfect solution.

People will misbehave, and to the extent that men and women are encouraged to pursue one-another with their former abandon, there will be an increase in abuse, hard feelings and even crime. There's a lot that can be done to minimize them -- though many of the techniques that worked well (not perfectly, but well) for millennia in traditional societies have been rejected by today's prevailing culture -- but we'll never get to zero. Trying to get to zero, an impossibility in any case, is a major driver of the attitudes that the author bemoans.

So by all means let the cute guy in the elevator chat you up, and do with your worry that he's a creep whatever you normally do with your worries. Just keep your wits about you, call on the clearheaded strength that many in the MeToo moment exhibited, and don't count on social pressure to protect you unless you want that guy to refuse to make eye contact.