How do you know any of this?

The central claim I made is that creepiness, like sexiness is about perceptions of the observer. Looking at the "evolutionary purpose of creepy behavior" is the wrong place to look and is likely to involve some confusion about the map and the territory.

I also mentioned offhand that the instinct to be 'creeped out' serves the purpose of reducing the chance of impregnation by inferior mates, either consentually or otherwise. It honestly didn't occur to me that this is something people would expect significant justification for. It doesn't strike me as a deep or particularly controversial insight.