It has got nothing to do with class. SRK may have a lot of class, but he's a lousy actor and no wonder only brainless Northies like him. He wouldn't pass for a crowd in a true film (Not the North indian Crap).
But, I agree that Rajnikanth has absolutely no talent. He has antics and some terrible movements which his fans claim to be style.
So, what's important are the acting skills and not looks or class or the color of the skin.