Drivatar Levels?

Just wondering if anyone has any thoughts or info on this. When I first started the career mode I had the drivatar level set to Above Average. Quite a few of my friends appeared in the field. I have since moved up to racing against “expert” AI. I’ve noticed that few, if any of my friends are in the field now. Do our drivatars get “ranked” somehow? Or have I simply prgressed further than my friends have in career mode? Like I said, just wondering.