RE: caliber or bullet weight
It seems like most hunters I hear of who've reach their 50's and 60's, have begun moving from magnums back to standard cartridges at or below .30-06. Maybe they don't like the muzzle blast or recoil. Maybe they've proven to themselves that burning more powder didn't do anything more to game animals than the standard cartridges. Maybe they were able to work on their shot placement over all their years of hunting, & found they could be just as effective with less "boom". Maybe they can't drag a heavy rifle around as well as they used to, & they don't care for touching-off a 6½ lb. rifle in .338 WM. It could be that, too, that at such a ripe old age, they're not particularly internet-savvy, and haven't learned that mild cartridges don't kill animals anymore.
FC