So this is here to stay and there's absolutely no way to stop it from happening. There's absolutely no way to trace this back to it's source every time. There's absolutely no way to prevent anybody from taking a photo from absolutely anywhere as source material to then manipulate it. You won't fix this by banning AI or whatever term is used for whatever enables this as you can't stop someone from running software.
It's not even a new thing, it's just becoming easier and more accessible and more lifelike. The nature of technology means it will eventually be perfected and widespread. Hollywood has already been using body doubles and computer graphics to allow actresses to not show their actual nude bodies in nude scenes for years.
What you can do without destroying all anonymity and privacy for everyone is find who uploaded or shared something with the goal of harassing someone. This is the means allowing for a detection mechanism to then remediation of said harassment. That's the real crime right, harassment? Shouldn't there already be laws and enforcement for harassment?
The root of this problem is simple. The desire to have sex with people, to see them naked, and to otherwise get off is not something that will ever go away for humanity, because it's ingrained in our nature to procreate. You can't fix this by brainwashing/training/whatever bullshit psychological solution that is often peddled as a silver bullet for invented problems either.
You can however change the law in your country so that standing menacingly behind a woman is considered harassment and punish them accordingly. If this was done by one or a group of guys in Boston and there were others around, odds are they would experience a lot of pain.