Wow, and I thought the US was bad! Where in the world has such insular norms for dating?However, my own experiences are totally different. Where I am from, if you are early 30s, the best you can realistically do is late 20s. Let's say 27-28 for a 31-33 year old male. Below that is just not going to work. Girls don't want a guy 10 years their senior. It not socially acceptable either
As for the OP, why are you worried about how masses of women will view you as you age?
Is it truly because you are afraid you won't be able to "meet as many friends at the club" as you currently do, as you asked?
This sounds like a PUA question coming from a place of fear of unable to indefinitely attract girls to fornicate with.
That's a bad idea, and this is the wrong place to be talking about it, but as you age the much larger issue is going to be hating clubs, not attracting a female once you are inside one. And the biggest issue with younger women is not that they may be slightly less attracted to you than they were 10 years ago, but that they will be immature, rude, have more mental problems and ADD behavior due to cell phone adoption, more ruined from the prevalence of Tinder, Netflix, and Only Fans, and they will simply be less feminine. You will still be able to attract them, if that is your question.
The *prime* ages for attracting younger/fertile women, at least for me in the US are from 30-40.
That doesn't mean it's not possible at 25 or 45. It's probably 80% as possible.
And that stat is only really useful from a sociological perspective, such as if we want to study human interaction out of curiosity or in terms of setting social policy.
But If you are interested in your own personal marriage prospects, it doesn't really matter at all. You only need to attract one woman. And you shouldn't focus on your age or her age. If you like her, pursue her. Don't make your age or hers part of the proposition at all. Men can attract women easily for decades. The only factor age plays really is fertility--either she is child bearing or she's not. It's a binary thing you should be able to see immediately upon meeting her.
I don't think there is any right or wrong time to marry, based merely on chronology.
But if I had to imagine the "best" scenario, it would be something like what Aristotle said:
18 for a woman and 37 for a man
That's about when both sexes peak. But fixating on the peak is going to let you down, the same way there will always be a peak hotter girl in the club than the one you just chatted up, or a guy with a newer, sexier car than the one you bought last month. If you want a real relationship you have to stop working about peak attractiveness and really physical appearance period, and focus on the more important things like relationship with God, habits, family upbringing, values, work ethic, etc.
If you want to continue "befriending" women at clubs, you can do so for as long as you can tolerate the club lifestyle, which will decline far faster than your looks will, but this is not the place to discuss it.