I wasn't going to review this but there seem to be a lot of polarized reviews of it, so here are some observations that might determine whether you want to put the time in:

--it isn't any sort of defense of Rowling, in fact it explicitly addresses the issue of how fandom can redeem the HP universe without endorsing her.

--it isn't high-literary whatsoever. It has funny and wry observations, but there's nothing stylistically interesting. The characters are as well drawn as they need to be for a compelling story, but there aren't enormous Insights lurking here, or unforgettable personalities. The teens are ordinary teens with slightly better than real dialogue.

--what I thought it did enormously well was capture the difficulties of late adolescence and how it feels to be fumbling around figuring out identity, and sometimes only knowing what you're against, in a world where there's so much to BE against but the "who are you" answers may be years away. The main character is pretty woke and most of what she/they does with it is to react against their (pretty difficult, somewhat fractured) family. And gradually figure out how to get more joy and less friction in life while working around other people's priorities.

--as a result we have a plot that's pretty static. The narrator is stuck. (I guessed the Big Plot Twist many chapters ahead, but there isn't much motion toward it, just a bunch of quidditch games and friend/family disagreements that don't necessarily move anything along.)

--nevertheless this is cute and its heart is absolutely in the right place and it's not afraid to represent how some really ugly stuff can exist in a family that's more or less functional and loving, how friendships have terrible patches, and yet people go on.

--the team sports angle is surprisingly fun and not overly whimsical despite being, y'know, Quidditch.