"The Wall" is a much discussed topic in TRP. And although there is truth to this concept, I think the root cause is not that female beauty rapidly decreases from 30+ but that most women never learned to compete (for HVM) in their 20s.

I'll elaborate: Women in their late teens/early-mid twenties are a very highly sought after 'product'. It's not particularly hard to get into a LTR with a decent guy their age, especially if you're a young woman above average in attractiveness you hold a lot of leverage in the sexual marketplace.

The necessity for women in this age bracket to cultivate other traits like femininity, cooperation, submissiveness is low because they don't need it to keep a man/men around. By the time they reach their late twenties/early-mid 30s their beauty starts fading and these traits become more important. (Men will gladly go down in looks to go up in cooperation) Not having developed these skills, suddenly they cannot hold the attention from the quality of men they dated in their 20s any longer.

At the same time men their own age start gaining more leverage as they become more successful in their careers, better social skills, more maturity etc. This is what TRP refers to as 'The Wall' the revelation that as a woman the quality of men you can get goes down as age goes up. To me however, it's more so about never having learned to compete for men, never having to have had put in effort to keep a man around. Not having learned to cook, massage, be sweet, cooperative, feminine, not having a good gym routine in place etc. These things are essential to learn in your 20s because you want to learn things before you need them, not after.

A question I think is worth pondering; 'How would I keep my man if another (objectively more attractive) woman set his eyes on him?' You should have a good answer to that question differentiating yourself from other women if you want a high quality man in your life and keep him long term. (I can't find the post but it's an honey analogy which is a great read if you struggle to answer this question)