IMHO, that's why implementing properly-working sliders instead of factory-fixed difficulty levels, in single-player mode, that is, is important. And their fake excuse about not having the time (in 4 years? Are they kidding us? What are they doing all day?) does not stand.
I play lame-ass keyboard since 2010 (I can't get my finger mechanics to work effectively on a gamepad, and I don't have the money, nor any space for a wheel) with full or medium TC, and ABS on. In my experience, from 2010 to 2012 and at my level(s), the AI overall laptimes were about 5 seconds slower than reality. Now in 2013, they're around 2 seconds faster than real life. Sure, this year I also can drive around 2 seconds faster than real life for Qualy sessions 1-2 hotlaps (on keyboard), but any 100% race at that un-realistic pace is finger breaking and keyboard keys destruction disaster!
Sliders would allow us to fine tune the pace to our liking (that's called: competence).