Reading through these posts, I still stand by my 20 year shelf life theory. Most talk about a time 10 years ago when they were fitter or played more.
I think there is only so much you can do until the bell curve of life catches up with you athletically. At first, you get more skilled and improve rapidly, then you learn mental aspects and continue to make strides, but at a certain point you just peak. Age slows you and weakens you naturally.
I don't think there is a player in the world that has played 20 years and still feels their game is on the upswing. And if there is someone thinkin that, they are dillusional.
Hmmm....in general, I want to believe as you do. But as I look at my own "life," I have to wonder when do/did I start this time clock.
I "played" in HS (read: a PE class turned into a Title IX/Diversity "team")...but then dropped it just two years later in college.
Picked it up again at ~35, didn't play real competitive stuff for another 2 years.
Then, at 40, proceeded to take ~4 years "off" to have two kiddies.
I'll tell ya, I was probably at my physical peak maybe 2 years ago, at 45. Healthy diet, chasing (and lifting!) two babies/toddlers...there wasn't much 2 Aleves, a glass of chocolate milk and a good night's sleep couldn't solve. But I wasn't playing multi-match/per day tourneys or staying up til double-digits hours.
Tennis-wise, however, I still feel like there's a little bit left to learn, a few more tools to stash in the toybox (a better serve variety, a bit more spin...both top and slice, and a better acumen to handle and dish out pace). And now that those kiddies are set to head off to school, I'll have a few more hours to hit the courts, either for lessons, self-drills or matches.
After many years of mostly doubles, I've actually gotten back into singles. And while I don't love it like I do the doubles, it has its own exhilaration. I have mixed it up, one-on-one, with those younger and older than me...and, quite frankly, have less issues with the younger set. The ones that can literally power me off the court, a tip-o-hat to 'em...but they're few and far between in the USTA set. No, it's the just slightly older ones, who play those big points super big, that are my nemeses. Still, I've tried to cultivate a playing atmosphere that they've enjoyed, at least enough to wanna give it a go again with me...be it USTA sanctioned or not.
So, is there a wall? Eh, only in our minds. And the older I get, the better I think...the older
guys get. Gray hair or bald, if they're fit...and/or trying...they get my vote.