I bought this book from a local store. The woman at the counter told me it had been an exceptionally popular seller lately. She asked if I knew why.
I didn't know why, and it made me reflect on why I was buying the book, which I couldn't remember either. Where did I hear about this? Why did I want to read it?
I remember now. I read Osamu Dasai's No Longer Human during a chaotic period of grief last year, so I was sensitive to the aesthetics of what you could call loser fiction, which I resolved to read more. No Longer Human is great, although it's also intemperate, lurid, miserable.
Stoner is not really the same kind of text. The title character isn't especially maladjusted or socially marginal. His life is, in aggregate, fairly mediocre.

But what is the Loser canon? Will somebody make a list?
Houellebecq, Dasai, Kafka, Williams, Brookner... what else?
All right, I'm making the list: https://www.lit.salon/lists/anaca/kV7aS11R0n5kzSKGpvsi/loser-canon
Maybe Dostoevsky, Ned Vizzini, and Salinger as well.
Definitely an ad-hoc category with some loose boundaries.
Salinger for the Catcher? Isn't teenage-hood inherently loser-y?
Lolita, Portnoy's Complaint, the Adrian Mole books.
But why Lolita? He ends up a pretty successful pedophile, doesn't he?
I haven’t read him yet but I believe Herman Hesse falls under this category.
I have read a lot but along time ago, and I don't know or remember which one would fit the loser archetype.