Rahman is a good music director of the modern era who has given a new direction and style to the bollywood music. Guys, do not compare with anybody else. I don't think other than older music directors(S D Burman, R D Burman, Laxmi-Pyare, Shankar Jaikishan, Naushad, Khaiyyam, Salil Chaudhury, O P Nayyar and many others) none of the modern music directors are legends. They a regood in their own style but only older ones are the legends. I don't know what will be the status of modern songs after say 20-30 years but those oldies will remain goldies.
For the time being, let's not talk foolish and waste time.