Yep. It's all about downforce. Downforce is what separates the boys from the men. In the not too distant past, the men (and women) drove racecars that had more horsepower and a lot less downforce. It takes guts to put the pedal down and keep it there for a long time while negotiating a curve driving these ground effects cars. It takes more guts (and talent) to put the pedal down while driving one of the older higher horsepower racecars that didn't have the downforce that today's racecars have.
The opinion I just posted here mirrors the same opinion that Johnny Rutherford offered to the motorsports media several years ago. He was referring to the shape of the underside of Indy Cars. He basically said that the bottom of Indy cars needed to be flat in order to force the drivers to drive the race car using the brakes and throttle in order to get through the turns, instead of relying on ground effects that allow the racers to just use the throttle to get through the turns.