Tennis is not as big as football or basketball or hockey, but if the guy is 6'1, tennis would make a difference. Can't be like 5'8 and be a tennis player, girls don't care then.
Big things are height and hair. A man has those 2 outside of school, he will be fine.
The height and overall physique would matter more than tennis itself.
I can give my high school tennis experience as someone who played on a tennis team all 4 years of high school. It meant nothing, likely due to the height issues I'll describe below.
The first 2 years of high school were mostly a loss. Around the 2nd half of sophomore year is when I got to be tall enough to be taller than most females. I reached 5'8" by around the end of sophomore year. I reached my fully grown height of 5'10" somewhere in junior year of high school.
I didn't ask out any women until my junior year of high school due to lacking in height. Even topping off at 5'10" is very average. Women don't get excited about an average height man. It's just sort of there for them. In junior and senior years of high school, I at least had opportunities when I was around 5'9-5'10" whereas I was a non-factor until around 5'8" in the high school dating scene.
My high school experience would have been worse if I topped out at 5'5" like
@MatureDJ .
@MatureDJ also had the problem of attending an all-boys high school + having lousy height. I got to have a co-ed environment.
Hair isn't an issue in high school. Most males have a full head of hair in high school. It would be an outlier to be balding or greying at that point. Greying can happen in one's 20s but hair issues don't usually start until at least one's 30s.
The only male hair issues that could be relevant in high school are body hair issues and possibly indicators around puberty. A late pubescent onset would be a high school issue.
I think the most important time is a man's mid to late 20s. If a man wants to get hot girls, have sex with them, get them pregnant, etc, he should do it in his 20s. If he waits until his 30s, it is too late for the "hot girls".
I agree that the mid to late 20s is an important time. At that time, I was starting to feel the pressure of turning 30 and wanted to do something big in my life. I changed cities once in my late 20s around this as I felt it would better position me for success in multiple areas of my life.
When considering life around the ages of 24-29, there's a lot to like. From 24-29, men are old enough to be older than a lot of women they'd either meet at nightlife venues or old enough to be older than a substantial number of women on swipe apps. 24-29 is still young enough to be considered age appropriate for the youngest of hotties. Having sex with attractive women will be comparatively easier with youthful age and good looks from 24-29.
Getting women pregnant is better around the 25-32 range for men. There's a lot to be said for somewhat younger parenthood, but it goes far off topic of this thread.
The important connection back to the thread topic is that a better high school and maybe even college experience will set up a man well for his mid to late 20s, and even beyond if necessary.
During the ages 24-29 stage of life, it wouldn't matter directly what a man was like in high school, but it might appear indirectly in the way he presents himself to women during this time.