Most men don't lose their hairlines in their late teens... That's a rarity. Does it happen, yea, but it's rare.
It's not as much the age as being ready to provide. Sure, find a gal that's cool with living in a trailer on half an acre of land. I personally don't see anything wrong with that. But you need to think collectively, it's better that men be older. Not necessarily by 10 years, but older and able to handle conflict. Handling conflict is something I'm noticing a lot of younger guys are having trouble with these days. That's the fault mainly of mom and dad. Mainly dad.
Women looking for marriage in their 30's is not ideal at all. Sorry. With men, it's usually not a big deal at all. If you're a homely looking guy in your 20's, your most likely a homely looking guy in your 30's, just with probably more money.
A lot of you dudes are not even remotely good with the opposite sex. This is learned over time. Socialization is important for both sexes.
Those guys in their 30s are visibly old looking (most guys start showing aging past 25) and at that age more men will have hair problems. Most guys are plain which is a problem in today's world as being plain or average means you don't stand out to the ladies.
I think most gals do not want a man who is too much older than then (unless the guy is handsome or looks young for his age).
Also skins issues like acne scars or dark spots/moles can be a barrier. Basically being average is difficult enough but each flaw (age, hair, skin etc) only adds to the difficultly and I've noticed that cameras make skin issues more apparent (most likely due to how the lens focuses on everything which makes blemishes stand out more).
What's your take on when a woman should get married? I feel bad for the 30+ yr old girl, she has a lovely personality but she is mixed and unattractive and there aren't many older guys, some of them are white and vaxxed while she is unvaxxed. So that's 2 more incompatibilities, her age only makes it more difficult. I'm not sure if her parents realised that girls need to try to get married young and wasted her youth in not looking or they couldn't find anyone or she is too picky (I don't know because i don't know them that well).
Clear issues on both supply and demand side of things plus other dividers like race, vaccination status among other things can be a deal-breaker. Finding the right spouse isn't easy.