A friend of mine reviewed this recently and explained it far better than I could: Book Review: On Earth We’re Briefly Gorgeous. I added a comment there:

I felt very much the same for quite a lot of the parts I have so far read. Bits of it I really liked, because they spoke to me specifically — Little Dog’s first queer experiences, for example — but a lot of it felt really uncomfortably misery-porn without me feeling I was learning a huge amount from it (except a bit more context of wartime Vietnam, maybe). And it was also pretty strange reading something that felt like it was autobiographical but also a roman à clef, y’know?

Interesting and bits of it are great — and [a:Ocean Vuong|4456871|Ocean Vuong|https://images.gr-assets.com/authors/1561472666p2/4456871.jpg] is clearly an exceptional writer — but I DNF’d about halfway through.