This is one of those movies that everyone loves, but it really doesn't deliver effectively enough. The sentiment is fine - I loved the notion of a platonic soulmate and confusion between feelings of platonic love and romantic love woven throughout the film. But plot-wise, it really fell flat and didn't make me feel that sentiment fully as it was scattered across too many irrelevant aims.
This movie attempts to make Aster seem mysterious, interesting, unique, and worthy of the attention of our protagonists by...making her have two stereotypically conflicting characteristics, and that's it. Her love of books and philosophy is just a vehicle to make her seem different and depressed even though in a high school sense she "has it all". But being two things that are "opposite" (aka being pretty and popular while loving books and being smart) does not make you divine. There are lots of pretty girls in the world, and all of them are human beings with more than two qualities that make them "not like other girls". Too often is the contended-over love interest in movies like this one just mysterious enough to seem interesting if you take them at face value, but truly flat when you take the time to really think about the qualities attributed to them. This movie would have gotten me really excited about having watched it if not for having no care or interest in Aster, the axis around which we are drawn to Ellie and Paul, which in turn makes Ellie and Paul seem less dimensional because they are for some reason both so in love with Aster.
As other reviews have mentioned, there is also very little character development in the film. This would be more excusable if the characters started off as more dimensional than they are. Ellie is the classic protagonist with one parent who doesn't fit in and struggles with her identity while she provides for her family. Paul is the one child of a big family who wants to make something of himself but has little self-confidence. Aster's boyfriend is nothing more than a cartoonish embodiment of the town trust fund child who's a huge douche but no one seems to care. And I've already talked about Aster. There isn't really one concrete lesson for any of these characters here - even the LGBT representation doesn't go anywhere or teach us or the supporting cast anything about acceptance or diversity.
Finally, I do very much acknowledge and appreciate Alice Wu's Asian and LGBT representation. However, to me, this movie doesn't achieve a motive related to that representation. It's just a movie that includes an Asian girl who happens to be gay. And while those parts of her identity play some role in the various challenges she faces, as I said, the audience and other characters don't learn anything of depth or value about what it's like to be Asian or gay or to accept someone who is both of those things.
The subtle meanings, repetitions, and the shots in this movie are great, and overall I enjoyed it. But at the end of the day, it's a pretty basic coming-of-age offering that could have done a lot better with stronger characters.