It's not obvious to me that personal physical beauty (as opposed to say, beauty in music or mathematics or whatever) isn't negative sum. Obviously beauty in any form can be enjoyable, but we describe people as "enchantingly beautiful" when a desire to please or impress them distorts our thinking, and if this effect isn't purely positional it could be bad. Conventionally beautiful people are also more difficult to distinguish from one another. There's also the meta-aesthetic consideration that I consider it ugly to pour concern into personal physical beauty, either as a producer or consumer, but it's unclear how widespread such a preference/taste is. (I would consider a world where everyone was uglier because they spent less time on it to be a much more beautiful world; but clearly many people disagree, for instance George Orwell in 1984 seems to find it distasteful and degrading that the Party encourages its members to have a functional, less dolled-up personal appearance.)