read the Paris or Kenyon review, or the New Yorker. Or listen to the NY Times books review podcast for more general book reviews and interviews with authors. They do have YA book authors on there as well.

Harry Potter was fabulous for reading aloud to my parents as a young kid. I occasionally listen to the audiobooks with younger kids in my family, and they love them, especially Fry's version. One of the best middle-grade books to get 8-10 year olds excited about reading and writing. A Wrinkle in Time, Percy Jackson, and the Chronicles of Narnia, too.

You're being downvoted, but moral engagement with art is valid, and always should be. If I make a neo-nazi romance, that casts genocide in a positive light, people could say my book was bad, and be correct. They could say the writing is good and the romance was sweet and authentic, even, and the book could still be bad.

The problem is that you're likely consuming the content of extremely young and likely inexperienced and undereducated people who've barely made it through a high school lit class. That's fine, but the source of the opinions you consume also matters if you're looking to expand your own intelligence and literary analysis. This depends on your goal, though. Finding someone who likes the books you like is great for those para-social relationships and building wonderful echo chambers, but also for finding real life book recs. But, the truth of the matter is that good opinions exist, and some people's opinions matter more than others within a certain scope of criteria. It's absolutely silly to say everyone's opinion has the same weight regarding art.

We can engage ethically or aesthetically, for example. We can judge the morals, the quality of writing, composition, style, etc. Those are all valid criticisms, and some may boil down to preference. I personally think we should all be critically engaged with the media we consume, including literary art. Nonfiction holds an even higher standard, btw, so if you find someone speaking of "all opinions are good, and no-one is better", please run as fast as you can after politely telling them what a load of utter codswallop it is they're spewing.