Is the lord of the rings reactionist?

In this newyorker pice Moorcock attacks The Lord of the Rings as conservative and supporting morally bankrupt values:

But Moorcock, one of the most prolific living fantasists, sees Tolkien’s creation as little more than a conservative vision of the status quo, an adventure that brings its hero “There and Back Again,” rather than into a world where experience means you can’t go home again. Moorcock thinks Tolkien’s vast catalogue of names, places, magic rings, and dwarven kings is, as he told Hari Kunzru in a 2011 piece for The Guardian, “a pernicious confirmation of the values of a morally bankrupt middle class.”

I don't get the reasoning. I have little knowledge of political theory, perhapt that is the problem. Can you explain what his critique actually is and what school of thought it belongs to? Is this some kind of critical theory / structuralist issue?