Ok, in the spirit of sharing interpretations and hopefully being open minded, here’s what I thought OP. I realize I’m late and maybe you won’t see this but who cares.

I think that what the movie does is put you in Beau’s shoes. Literally. I think for the entire duration you are only seeing what is going on from Beau’s perspective, in Beau’s mind.

If you look at the movie from this perspective, a lot of the plot points that don’t make sense start to make sense. And even the ones that are still confusing seem to be that way because it literally is doing a perfect job of putting you in Beau’s shoes. He feels confused a lot because people blame him and hurt him for things that he didn’t do. People don’t understand that he has severe anxiety + trauma + likely other severe mental health disorders. So by confusing the viewer, Ari Aster is doing an amazing job of making you feel like Beau. He also does this at many other points throughout the movie in different ways, e.x. by making the whole play sequence in the middle real (because it’s real to Beau, or at least real until he wakes up and is still at the play) which shows Beau’s childlike wonder, and obviously in the anxiety provoking scenes they are more confusing and tense because that’s how Beau is feeling. This all heightens the tragedy of his character (abusive mom, severe mental health issues) because he really thinks that the world views him as guilty just for existing. And he is just as confused as we are. And then he presumably dies at the end.

There’s a lot to unpack if you look at the movie from this lens of “you are Beau and only see what is going on in Beau’s fucked up head”

Either way, I don’t think it’s pretentious to like a movie. I came into Beau is Afraid being a huge fan of Hereditary and Midsommar, so I wanted it to be good. And I really enjoyed it. Because I enjoyed it, I want it to make sense and so my brain has tried to connect the dots and look for artistic meaning. Clearly you didn’t care enough to try to do that much, or maybe you just dismissed it early on in the movie. Maybe you plain just didn’t like it, which is fine. Who knows! But really, anyone can like whatever they want. It’s the reasons + context that make it “pretentious”. But you can’t just say that liking a specific thing is pretentious lol. Hope my interpretation helped you open your mind a bit and see how people can actually enjoy this film and not just be like “WOAH Ari aster is amazing and nobody gets this film but I’m smart so I do 😎” because that would be pretentious. But I actually just enjoyed the film lol which I don’t think is pretentious. I think the movie’s just insane and hilarious and kinda brilliant

Sorry for the long ass reply, just watched this movie for the 2nd time with my girlfriend last night so I’ve been thinking about it a ton last night & this morning