Interesting. A lot has to do with what qualifies a good musician? What I try to do in a jam
session is feel out where the musicality is by playing very simply. Playing with some so-called better musicians may not work at all if you are dealing with hot-shots and ego-driven players who might be good by themselves but not so hot in a group setting.
A lot depends on the familiarity with the style of music. Sometimes a sophisticated jazz player may not function well in a folk group and vice versa. It's as tough for some technical jazz players to play simply as it is for the folkie to find his/her way through Giant Steps.

I define "worse musicians" regardless of their level of expertise as being insensitive to their
musical surroundings. With musicianship, environment is everything.