I would be interested in finding out how much real-world driving experience those guys have that come up through programs like GT Academy. Have they never driven a car competitively, even maybe just autocrossing, much less something at speed? (And that's not to put down autocrossing... I don't think there's any better teacher of a car's dynamics than autocrossing.) In other words, is the transistion from virtual racing to real racing a complete transition?
I would think that anybody seriously into sim racing is also a bit of a petrolhead and has some driving skill in the real world. I was a decent autocrosser "back in the day," although I've never done anything at speed in the real world.
This thinking makes me wonder how much of a jump the sim-to-real actually is for some of these guys. If they've never even squealed a real tire, then everything they learned is in the sim, but if they have a bit of skill already and don't mind it if the car gets a bit sideways on them, maybe it's not that big a deal moving from sim to real.
The biggest thing a sim can't possibly teach you is the forces involved, and much of your driving feedback comes from feeling those forces in the seat of your pants. Even a hydraulic rig can't fully simulate real-world feedback, especially for the more powerful cars. Sims give you audio clues, like the annoying tire noise in Gran Turismo when you're at the limits of cornering traction. Unrealistic, but no other way to know that you're that close to the limit. How does a non-driver, translate that in his mind when he gets in a car and there's no tire noise, just wind, engine, and gear noise, but he can't hold his head up after 5 minutes?