A pretty good recent large-scale study of runners (not ultra or competitive runners) showed that if anything, runners had long-term better cartilage health.
In the ultra crowd, lots of older folks as well; doesn't seem that their cartilage is wearing out prematurely. It's one of the most oommon but inaccurate myths about running injuries, that you have a finite number of miles in your cartilage, and thus destined for a wheelchair at age 65 just because you ran a lot when you were longer.