[gnicholas]

It's possible that people have evolved to be more attractive than a long time ago, but the issue is not of absolute beauty but rather relative attractiveness. There will always be a top 10% and a bottom 10%, even if the entire population increases in attractiveness across the board.

But separately, it's not clear that attractiveness is hereditary in the same way that height, for example, is. If two tall people have kids, they will almost certainly be tall. It's also incredibly unlikely that two short people will not have kids that are tall.

With attractiveness, heterogeneity between generations is much more common. I know some very attractive people who have not-very-attractive offspring, and vice versa. It depends on how the features of the two parents mix together.