I see a lot of adult women on reddit claiming that between the ages 12-18 they were at their most 'shallow' phase in their life as far as picking potential partner goes, by this they mean that they developed crushes on boys for the most superficial reasons; primarily looks, style, popularity... and that nice guys just have to wait till as girls once in their 20s will gradually start appreciating other qualities besides looks, like personality, humor, life goals, etc..

I couldn't disagree more with this.

When I was in high-school me and my not-so-conventionally attractive friends all managed to have romantic experiences with girls, and it was way easier that in college. Even more, I was far from a "Jock" (i was asian, pale, and underweight) and even I got cold approached by a conventionally attractive girl in school. High school was the last time I really saw couples that were, for the lack of a better term; "looksmatched" in the sense that you could see skinny girls date scrawny boyish types like me.

Fast forward and we're in our mid 20s; I decided to creep on social media of my hs sweethearts; the guys they are dating now are all the complete opposite of me; tall, white, conventionally handsome, lumber-jack types with a stubble. The most hilarious experience I had just weeks ago was running into a girl who had a crush on me when she was 15, but I was 5 years older so I didn't pursue anything, and I've gotten the "LOL I didn't know what was I thinking back then" treatment from her. Oh, did I mention that she also dates a jacked 6" tall white dude sporting a undercut?

tl;dr girls standards as far as physical attractiveness comes actually get more uniform and narrow as they enter their 20s, than in high-school where they are more plural.