No it isn’t. The fact that women only find the top bracket of men attractive doesn’t lend any credence to to sub 8 theory ffs, most men in relationships are with their partners because it’s the best they can do, not because she would be their first choice if they had unlimited options.
If I’m being totally honest, I only find the top bracket of women attractive as well, but that doesn’t mean I wouldn’t settle for less if given the opportunity. Everyone, man or woman, is only as superficial as their options allow them to be. If I was a Chad and had the option to, you can bet your life I wouldn’t waste my time with anyone who wasn’t a Stacy.
Relationships are superficial at their core, and are predicated on convenience and one's available options. Most humans, if given the choice, would only pursue the top 20% of the other gender because that is the pathetic superficiality of our sexual nature as a species.