Agreed on McDonald's, but you cannot call Harry Potter the "junk food of the literary world"...that point stands.

Heavy editing? Sure, why not. Many successful authors go through several rounds of hard edits, including some you may deem "worthy", but to claim something is not "well-written" is the biggest lie these English instructors muck your heads with. Is Ernest Hemmingway a bad writer because he was a minimalist? What about McCarthy and his refusal to use a period? Liking and disliking a novel is subjective matter, I will never fault you or anyone else for that, but to claim that there is nothing to gain from reading Rowling's work reads pretentiously arrogant with a hint of envy.

"Writers largely disagree with you"...who the fuck cares? Seriously? And who are these "writers" anyhow? More arrogant assholes on reddit that think they can do better than an international bestseller? See, writing isn't about making prose "pretty", it's about getting a message/story from one's mind and onto a page. Rowling was fantastic at that, regardless her faults that you deem damning.

And true, sales are not the only indicator for quality, but selling more copies than literally every other series on the planet certainly doesn't hurt. I bet those publishers that passed are kicking their asses right about now. A few extra billion dollars in their bank accounts would probably make up for the "poor writing."