I suppose that our lack of appreciation for subtlety applies to auto racing as well. Watching a Formula One race where the driver who is in the lead at the first turn of lap one will win the race is far too subtle for American audiences. We prefer watching 20+ drivers running bumper to bumper three wide at Talladega all trying to figure out how to get to the front without getting hung out to dry or wiping out the whole draft.
No. Formula One doesn't do well in America because American's like to watch the whole game, which you can't do in road racing. NASCAR has overtaken Indy because Indy because the IRL and CART feud is stupid and the warring factions have been very creative in finding new and exciting way to kill their sport. Also Indy has lost all the interesting drivers, and NASCAR has found a way to mass produce interesting drivers that give great interview and are highly approachable by the fans.