Ah yes, The Mummy is in fact a Disney Pixar cartoon. Imhotep is, actually, despite the name of the film, a bunny.
Of course, how could I have forgotten that...
The Mummy (especially and in particular, the first one), is a blend of thriller, horror and action (I'm just repeating my first post again, but...). You compare it to films which are along a similar line, such as the Indiana Jones films, and you can see it is similar to those sort of films in some ideas, but, with the 'horror' cranked up a notch. It's NOT an out-and-out horror film (I never said it was, and again, I've made this point), but, it DOES contain elements of horror (it's listed on IMDB as one of the film's genres, if you don't want to take my word for it). It uses techniques like tension, darkness, sudden jumps, all of which are clearly and essentially horror movie techniques.
I think this horror idea is then actually REALLY played on with the rides. They don't focus so much on the action side of the films, but, on the horror side. I think this is clear enough just from the queue - dark, claustrophobic and with traps that essentially, go "BOO". Darkness, shadows, cursed Mummies jumping out from all over the shop, scarabs, death... the rides focus a LOT less on the action sequences in the films (planes flying through walls of sand, the boat scene, things like that) than they do on the ones one could term 'horror'.
No, it's not a horror film. But, the rides, essentially, ARE. Just go back to the press releases for them they talk in terms like "grisly", "haunted", "scary", "darkness"...
Obviously, Thorpe can gloss over this by saying it's the first "out-and-out horror film themed ride", that would be true. BUT, to say the Mummy and the associated rides do not contain elements of horror, and so, horror can be termed a genre of and an influence on the rides, is a bit silly in my opinion.