Yeah - the older players almost never hit their RL numbers on any stat. There were so many more possessions due to the pace of the game that their RL stats were "inflated" by WIS standards, which they tried to fix by "normalizing" values using "advanced" statistics.
All it really did was nerf everybody pre-1970 except for Wilt. And it nerfed Wilt, but he's still amazing. Other than a few Russell seasons, most of Wilt & an Oscar or three, those older players are really not worth using in most league settings. I feel like you're paying the salary for RL stats they will never achieve (without severely gimping your squad).