If you’re going to get into modernist literature it’s important to understand that it was a time when writers were trying to get away from the formal structures which had traditionally defined literature in favour of an expression of aesthetics and a mélange of emotional experience.

To try and assess a book like Der Zauerberg within a framework of traditional literary structure is like assessing a painting by Paul Klee on the basis of how physically accurate he renders his subjects, or to say that a cake is badly cooked because it doesn’t taste like a rack of lamb.

I'll give you the latter, I guess I mean just "learns". To be fair, there is an entire subgenre of Russian novels about young men who do nothing, don't change or grow at all, and then die.

Complexity can be seen in more than just the book's plot. Henry James has some very simple stories (The Ambassadors), but uses complex prose that elevates it above what it would be if anyone else had written the same story.

On the other hand, Hemingway uses fairly plain prose to write stories which are sometimes incredibly simple on the surface level (Big Two-Hearted River and Old Man and the Sea, for example) - and yet their meanings and the complexity of their characters are debated to this day. Would you say that everyone who studies those works is wrong, and you can simply dismiss them out of hand because not much happens at the story level?