Yeahhhh noooo.... that is not a good response at all, that likely gets you the "you tricked me into being attracted to you" or other victim-blaming BS response and you probably get assaulted or worse.

Terrible idea. At best he'll just have more fuel with which to keep harassing her, at worst the situation could turn violent and your 'advice' will have made a bunch of onlookers take the creep's side.

in my experience you are correct, but there's a significant chance they'll react violently rather than just giving up and walking away.

also a surprisingly high percentage will not care and even double down (and occasionally you find these creeps intentionally looking for trans women). this is common enough that we have a slang term for them, "chasers".