Responses
Not sure that's a true case. A lot of webtoons that are super angsty, and worse, long soap opera type melodrama are rated higher. Most of them have bad art, too. I think they were rated higher because the faces were drawn pretty (aka, K-pop and k-drama standards).
I also noticed that older mangas (10-20 years ago) are rated lower ┑( ̄Д  ̄)┍
You know stories like this are always 8.5+ rating. Maybe people don't like things that are super angsty and dramatic but I like spicy things