I think the focus on beauty exclusively is because femininity has been downgraded. Most men are drawn to feminine women, not necessarily very beautiful women. Being feminine makes women attractive.

But the emphasis from the feminists that they can do all a man can do pits them against us. Plus women are encouraged to be more masculine and assertive.

When you succeed in equalizing men and women to some extent all that is left are biological differences, the most visible of which is the externalities. Beauty is then elevated as it is exclusively female. Prettiness might be the better word.

Equality, then, bulldozes natural differences leaving only very visible biological differences.