Can't say which one is THE top.In your opinion, what is the "top fantasy media"?
But the top 10 would be some combination of the top 5-7 fantasy video game series and cartoons/anime, D&D, Warhammer 40k, and ASOIAF/GOT.
LOTR and the Hobbit don't crack the top 5 today. And won't make some top 10 lists today.
Lack of critically beloved LOTR games, movies, and shows recently hurt it. And people don''t read books to know enough lore to bring in more fans.
Media has changed.