There are four types of movies
1) General bullshit (complete crap)
2) Movies that are good fun, but nothing deep (popcorn flicks)
3) Movies which are well-crafted and interesting in all facets
4) Movies that are, plot-wise, dull, but for which a new level of appreciation can be reached when you analyze it from an artistic and technical point of view.
Guess which category 2001 falls into?
If you take a good film class in college, you'll learn why #4 is so important. I've watched some terribly boring movies in the classes I've taken which suddenly become about 100x more interesting when you get to discuss them with other people. That's because what's actually interesting is imbedded deep within the form and style of the movie. When you talk with other people you start noticing things you never did before and you start formulating new theories and eventually the puzzle pieces start falling in place and you realize what a grand masterwork the film actually is. This does not stop it from being boring to watch, of course, but you suddenly realize what IS good about it.
I was forced to watch Last Year at Marienbad in one class. This is the longest, most boring, most absolutely confusing movie I've ever seen. And yet, we found so much to talk about when we actually began discussing it in class.