I think that's true to an extent. There's also the question of natural talent and body-type. Not everyone will be able to bench 500 lbs, no matter how hard they work. In the same way, not everyone will be able to run a 4.3 40. But yeah, you'd have to be a natural freak to lift 500 without hitting the weights pretty damn hard.
Having said that, I always thought that the bench was a pretty useless measure of how well someone plays ball. You rarely, if ever, replicate a bench press when playing football. I think it's a good measure of overall upper body strength but football is about using the strength you have in the right way and being explosive.