I understand what you’re saying, but sometimes it’s hard to distinguish whether a book is YA or not. Take Red Rising for example. I googled it to see what all the hubbub was about, (specifically asking “Is Red Rising YA?”) and that series is marketed as general fiction in some places, science fiction in some places, and also marketed as YA in others, plus I saw a lot of “This isn’t YA at all because there’s so much violence” type of comments.
Basically, I spent too much time looking into this, learned nothing, and added Red Rising to my TBR.
This is also my least favorite, but Jo and Bhaer remains my favorite literary love story.