Genuine question to those who enjoyed Haunting Adeline: how?

I know the extreme themes have been discussed to death, and that's not what prompted me to make this post. I just can't fathom how anyone who enjoys reading can read something written and edited so poorly, riddled with so many errors, and still find enjoyment in the reading experience. It felt like it was written by an edgy teenager who just learned to curse for the first time. There are so many cliches and countless unrealistic elements that I feel as though I can't possibly be reading the same infamous novel everyone's talking about. A bestseller?? I mean, she even misspelled her own character's name (Seraphina/Serafina).

If only a handful of people had bought this, I wouldn't be surprised, but how is this standard, this writing quality, accepted and overlooked to the point where it's grossed hundreds of thousands of dollars. I understand writing is subjective, but errors and typos and plotholes are objectively bad. How did two editors work on this book and it still went to print in that state, filled with rookie typos?

To be fair, I'm incredibly biased as an editor myself, but that's one of the reasons I've had this book recommended to me by so many people. Because I work with books for a living and many of my clients self publish, they said this was something I HAD to check out, like I was going to be impressed.