I'm 62, shoot year round, and actually went up in weight this year as I can pull my new RX7U easier than my earlier bows.
I have a weightlifting background and it is probably helping me now. I live on a farm and work all the time, too so avoiding strain on my shoulders is not an option. Feed bags weigh the same as they did when I was in my teens.
My previous new bow is an RX3 and I cannot pull 70# with that bow for many shots without losing proper form, like 10-15, max. But this new one, 100 shots are no problem and it's over 70#.
RX7Us are not the fastest bow around but they have a very linear draw cycle and that is why I've kept my limb bolts tightened all the way down, because I can shoot it ok at this weight and it probably needs it.
I'd have no problem turning it down if need be, I think my HyperEdge target bow is in the 55-60 pound range and it's real easy to shoot for several hours.
So, yes, I think weight probably does as a rule go down with age. I still shoot my .41 and ,44 Magnums the way I always have though, recoil is recoil and one just accepts it and focuses on proper form every shot if you want to do it and get the right results..