If by "foible" you mean evolved preference that we can't do much about.
Over emphasizing physical attractiveness is how you end up with a burnt down house and a hot ex girlfriend. It's not some evolved trait we hold, it is very much a weakness. People are going to have preferences but it shouldn't blind them from the other characteristics somebody possesses. That's what they mean by over emphasizing.
I get that is the point they were trying to make but it didn't really fit with the comment being responded too. That one was pretty clearly talking about the weakness or "foible" of over-emphasizing physical attractiveness which isn't something we are helpless to overcome. Dating an asshole or crazy person just because they are attractive is an awful idea yet people do it all the time. It's not a moral failing either, it's just very short-sighted.