That is way overstating it. His elves are not really like anything before. There are elements of Norse myth such as dwarves, goblins, wizards, dragons, magic items, the Rohirrim, but this is just backdrop mostly. And all that stuff hadn't been put together like that before, in novel form. The "main story" of Middle Earth (the ups and downs of elves, men, and angels) is far out and doesn't have a direct precedent that I'm aware of. Lots of the characters rock, esp. Aragorn, Eowyn, Frodo+Sam and Faramir+Boromir+Denethor, not to mention Gollum.
I never said he wasn't a good writer and that the stories weren't engaging. And he created the first mainstream, persistent fantasy world in English literature (I say "mainstream", because as mentioned, people like Lovecraft had done it before). But the fact remains that once you get over the fact that he was first, Middle Earth isn't really a very unique concept.
I just get tired of seeing Tolkien's world hoisted up on a pedestal.