I wonder how many of those people understand anything about vehicle physics, let alone simulating those physics in real time. I have a master's in mechanical engineering and have written my own vehicle physics simulations. I can tell you that by far the hardest thing to simulate in a driving sim is the friction force between the tire and the road. As simple as the classical definition of friction force is (force opposing direction of object motion, proportional to normal force pressing the object onto the contact surface), it's actually hard to simulate numerically in discrete time (time steps) and produces noticeably unrealistic effects. For example, in some games, when your car is stopped and the breaks are locked, the car still slowly drifts around like it's on ice. That's because the applying a friction force according to the classical physics definition like this: "Friction Force = Friction Coefficient * magnitude(Normal Force) * -normalize(Velocity)" is inherently unstable. Using this approach, when velocity is zero, there's no friction force, so the car drifts for one frame. Then it has a velocity so friction kicks in and pushes the tire back for one frame. Maybe it doesn't push enough, so the tire continuously slips. Maybe it pushes too much so the tire ends up vibrating back and forth on a small scale. The net effect is the tire slowly moves around when it should be stuck to the pavement. Getting around this is not trivial. And that's just for the simplest case of friction, not even talking about friction between a tire which has a deformable surface spinning extremely fast and pavement with varying properties (gravel, wet, etc.).
All this to say, I understand something about vehicle physics simulation. Then I hear people shitting all over Slightly Mad because they did the Shift games and they say the physics in Shift were arcade trash. I actually thought the shift games were not that bad, yes there were tons of driving assists, but they can be turned off, and yes they hacked together a completely different drifting model which has unplayable in Shift II. But I'll stick my neck out and say the basic driving model was pretty solid and enjoyable. The biggest problem with both games wasn't the physics, it was input lag. When people say the physics in Shift are shit, they're not talking about the physics, they're talking about the lag, and the lag was unacceptable and wasn't fixed in Shift II, but it was a graphics issue and had nothing to do with physics. It couldn't be fixed but it could be improved by adjusting an obscure video card setting. After that, I was able to enjoy both games, even though my preferred sim is rfactor and I fully appreciate how good rfactor is. So I'm not writing off slightly mad. I think that, being outside the EA umbrella and managing the project themselves, they could produce something really enjoyable for sim fans. TL;DR most of the physics snobs don't know what they're talking about