I couldn't get through Tolkien. I tried reading the Hobbit but gave up when it started talking about blue beards and gold belts. It felt too arbitrary to hold my interest.

But the LotR movies are needlessly slow. It's Peter Jackson's directing style, which only works in that very specific context where a large portion of the audience is ready to fill in the blank spaces, and the rest of the audience forgives it because they expect it to be a rambling epic.

Every shot is one second too long. You could cut an hour from the runtime just by cutting out the lingering reaction shots. Every time Sam or Frodo says something, it's followed by two seconds of them staring longingly into each other's eyes. There are so many things to love about those movies, but they're basically unwatchable to me.

As for Rowling, I think her success is mostly due to accessibility. They're easy reads in a way that fantasy books almost never are. The reader doesn't have to put in any work to get to the world building.

She follows a classical plot structure. She establishes motifs early and only subverts them when subverting them becomes the obvious choice. There are many blue beard/gold belt moments, but they're propped up by easy-to-understand structures like the house system.

But yeah, then there's no depth to it after that. I always thought it was overrated.