I can't figure out how both of them played so long and so healthy. They did not have any advantages of modern surgeries, player resting, player friendly schedules, etc.

At 39 Stockton averaged 1.9 steals and a TS% over .60 (13.4 PPG on 31.3 MPG)! How is that even possible?

IMO, Kareem > LeBron, but both are clearly on the Mt. Rushmore of NBA (with MJ & a debatable 4th player).