The industry indeed needs J. K. Rowling, Sally Rooney, Colleen Hoover, celebrity biographies & memoirs etc. to survive. Good books will find their way to be published, and get discovered, maybe dozens of years later. I happened to read a novel by an English author published ~100 years ago. It is a good book, IMO. The publishing house had only one person. The entire office was one room in his apartment.

It is true. I would like to qualify it by saying "At the beginning, the editor is not your friend." A friendship, even very strong one, can be developed along the time, based on mutual respect and appreciation, temperament match, etc. Even then, a good editor will still be professional and be honest when they edit the writer's draft.

A good book may not be a "successful" book, especially in literary fiction, since the post talks about novels. The reverse can be true as well. It happens often that the editor tells the author it is a good book, and the publisher allocates resources to marketing it, schedules book tours, etc. while at the same time both the writer's agent and the editor/publisher expect the book may sell only ~2,000 copies. The target audience are expected to be other writers, a subset of avid literature readers, etc. They don't expect it will earn back the advance paid to the author. The publishers have portfolios and long term visions. Of course, this doesn't apply to small publishers, most of which cannot afford it.

I don't disagree to the gist of your post. However, in biomedical and public health research, papers are published even "if you don't find an effect", for good reasons. There could be simply very many unknown factors at the initial phase of some research topics. Researchers find or notice some things, publish them with rigorous discussions, proposed hypothesis with explicitly mentioned assumptions, etc. Other researchers build upon the existing results, add more discoveries, which can be proving or disproving, partially or wholly, etc. It often takes years of multiple teams to get a good enough understanding of a topic. This implicit collaboration is a positive feedback loop to advance the research.

The issue is that the vast majority don't read the detailed discussion in the papers and thus could get a partial thesis, which in many cases lead to incorrect conclusions. Media reports don't help, because they are essentially a simplified version. Otherwise, they can simply refers to the original papers and ask the audience to read them. Also, not many reporters have solid scientific training in the fields they report and don't understand the papers well enough. I don't blame them, since it is hardly their job. Good readers must be aware that the reports can be misleading, or biased, or simply wrong.

edit: grammar