This is one of the things I love about rock climbing. It really seems like an activity that people can gracefully continue into their later years (if you're lucky enough to stay able bodied enough).
Activities that are hard on your body, and 100% physical, can be really unforgiving when it comes to the aging process.
With rock climbing you can kind of shift your focus.. maybe do more trad climbing instead of sport or bouldering. Focus on different types of climbs, maybe more technical slabby climbs where you're on your feet more. You can still feel like you're genuinely participating in the activity you love, even if you can't do exactly the same things you did before to the same extent.
I love climbing, but lets be honest - in later years it is quite brutal on your fingers and overall wrists. Things like osteoarthritis affect climbers too, heck based on some discussion with a doctor doing a lot of ultrasounds of hands its expected that climbers have messed up joints in hands and she could see some damage on mine too (I climb for a decade, in my early 40s).
For every guy climbing till his 70s there are a lot of those who had to stop for reason XYZ much before. If its not this its shoulder, anything in legs, spine and so on. Genes play a huge part too and thats pure lottery.
Just over a year ago I was climbing in Owens River Gorge and ran into John C. Hoffman. He was 78 and doing laps on a 5.11c, with his wife Anne belaying. He casually mentioned he had bolted the route we were on back in the 90s.
I'm not sure his current limit, but at 74 he was redpointing 5.12c. He's a dedicated ORG local and has been climbing since the mid-70s. His advice was simply: don't stop.
I have back issue (possibly an injury, but will need a MRI to confirm as nothing shows on CT) - I find that the issue is helped by climbing, and light weight-lifting involving the back-and-shoulders - just lifting dumbbells with arms outstretched, enough weight to offer resistance that engages the muscles properly.
I find the "puzzle"(or crux) in the climb make it less boring then repetitive movements at a gym, plus the genuine sense of fear from the danger helps me push my limit a bit (though I did have a poor fall as a result, so needs some caution).
Also, practical if you like to work with your hands, and I think for guys having decent arms and shoulders are particularly attractive.
In fact I do gym climbing as well, and it's really clear that the sport skews very young. There are a few older people there, some of them very talented, but you see an awful lot of college tee-shirts.
I was never a great climber -- I miss doing V3s, but the V2s keep me interested. (A lot of that is actually due to pandemic, which cost me a bit of the very specialized bits of muscle that go into crimpy and slopey routes. I am gradually getting some of it back.) I should do more top roping, which affords a bit more room to solve problems without falling off and starting over.
Activities that are hard on your body, and 100% physical, can be really unforgiving when it comes to the aging process.
With rock climbing you can kind of shift your focus.. maybe do more trad climbing instead of sport or bouldering. Focus on different types of climbs, maybe more technical slabby climbs where you're on your feet more. You can still feel like you're genuinely participating in the activity you love, even if you can't do exactly the same things you did before to the same extent.