He did invent Orcs.
ORC, stands for Oxford Rugby Club. The people on the team were brutes, and he designed a brutish race after them. The term Orc is not in the mythologies of ancient cultures. Trolls and Elves were but even so not in the form Tolkien portrayed them, which is the modern form. Tolkien was the first to makes elves appear as tall, fair, wise and ageless. Prior to that elves in ancient mythologies were genreally like pixies or sprites. Tiny winged creatures etc...
Tolkien is the father of modern fantasy, yes there are similarities but it is presented and doen in its own unique way in the Elder Scrolls series. Not too mention the many new creations and takes on other creatures. Eg: Dwares are always portrayed as having the best crafting and being short. In the Elder Scrolls they take it up a notch and make them incredibly technologically superior and not short but of the normal height.
Im not arguing with the Orc fact, I didn't realize that and now I know. As for Elves I always thought of Nymphs/other Fey creatures to be pretty much elves or similar. Elves in my mind are like Bosmir.
I have no problem with admitting what he has added to the community, the problem I have is people actually trying to use it as some sort of weapon against the game's originality. Tolkien made the ideas, D&D did a lot from their but as parents who make a child these creations have a life of their own now and belong to none.
I think he would be happy to see that his ideas and writings had such a large influence on a great many things. I would be.
I have no dislike for LOTR, I just hate straight up comparisons such as when people say every other MMO is a WoW clone. That is all.
We all have imagination but besides things from scratch we often take other ideas/our history and tales and turn them into something else within our fantasy.