I think what's happened in the last few years is not so much the physicality of the car but just the actual forces generated on the body itself. The cars all have some form of power steering now but the brakes are still hard work over a two hour race. The two main differences I suppose are firstly the last set of regulations, which brought about the massive increase in aerodynamics and tyre grip. So they are more physical from the point of view of being thrown around. The second difference is drivers no longer have the luxury of going flat out all the time, they have to look after the car to enable it to last X number of races. Whether that is engine, gearbox, etc. So yes from that point of view you have a point. On a different tact, the performance difference between something like a GP2 car and F1 is also much smaller now. When you think of the 80's or even 90's the performance jump between a junior category car and F1 was huge, that doesn't apply quite so much now. However it's unfortunate that due to the technology in something like GP2 the driver budget is approaching almost the same level as an F1 seat now.