In my experience realistic physics are the most intuitive to pick up and play.
Purely from a physics perspective, Assetto Corsa is the easiest driving game I have played when it comes to adaption. The factors that made it inaccessible to many was poor gamepad optimization and hardcore elements that most casual players cannot be bothered to worry about (tire temperatures, surface rubber amounts and such).
GT Sport comes close, but in some areas it is dumbed down, and as you said, dumbed down aspects of physics can catch players subtly off guard if they expect more realistic behavior. It’s the nature of sim-cade, but I don’t consider this to be an overly decisive issue for the learning curve or enjoyment.
Absolute arcade physics, however, is something I have never felt comfortable with out of the box. The only way to improve your skillset, is to adapt drastically to their flawed physics, and even then it’s like the brain still cannot grasp how unnatural it feels. If an arcade game plays intuitively out of the box, then it’s probably because it can be labelled as sim-cade, which I’d say is a very scalable category in between simulation and arcade, and where the majority of today’s mainstream racing games reside. I’d argue arcade has gradually more become a relic synonymous with the the old days of Commodore, Sega and MS-DOS. Pre-historic racing games like Outrun, Lotus, Test Drive, F1 Grand Prix, etc. were really difficult to master, and much of the trouble came down to nonexistent simulation. The Crew 2 is modern example of pure arcade that is constantly at odds with intuition, and effectively why I find it harder to drive than Assetto Corsa.