I fucking hate thos saying. The moralizing of vanity is just another way to feel superior. The people who put a lot of work into how they look do so for a multitude of reasons. Sometimes it’s because they are just having fun but other times it’s because they grow up being told that they are never enough. That they are simply being deficient for not trying hard enough in which case their lack of vanity becomes instead the moral failure of gluttony or sloth. There is no win state. So then you are simply reinforcing that who they are aside from their appearance is worthless because they are empty voids for caring about the one thing that might be a rare source of validation. We all experience the effects of the privilege of attractiveness or it’s lack. A lot of us spend lifetimes unpacking the toxic effects of that programming. This isn’t the way to go about stopping that cycle.

“Vanity makes a person ugly inside” is just another way to put someone down so the person wielding this cliche can feel big. It’s moralizing someone’s relationship to their physicality and preying on places where people are trained to be weak.