I think part of the problem is that some really can't disassociate the writer from the writing. There's a difference between saying "X book" is terribly written and saying "the author of X" is a terrible writer. The first deals with the book; the second attacks the person. And I have seen that happen very often here and on other forums. In some cases, it is envy; in others, it's just honest bewilderment as to how the book became so successful. The problem is making that distinction and not falling prey to the author dissing.
As to when people talk about 'entertainment' versus 'serious' writing, I think it's a bit like the discussions about literary versus genre. There's nothing wrong with writers who write 'entertaining' stories; there's nothing wrong with readers who read them. But I think writers tend to look at all writing from their own standards - they write a certain type or style of book and compare other books/authors to that. And that just naturally means objectivity goes out the window.
As to when people talk about 'entertainment' versus 'serious' writing, I think it's a bit like the discussions about literary versus genre. There's nothing wrong with writers who write 'entertaining' stories; there's nothing wrong with readers who read them. But I think writers tend to look at all writing from their own standards - they write a certain type or style of book and compare other books/authors to that. And that just naturally means objectivity goes out the window.