Thank you for gobbling all those writing guide books. Can you elaborate on what you liked and did not in those books?
Also, screenwriting guide might be put in a separate category, no?
I found that they highly value the ability to condense information into the shortest screen time possible, which might diverge from novel writers' values. For instance, a movie might need to reduce a character to being an thematic idea mouthpiece and design the plot to become a factoid. While it allows a story to finish in a couple hours, it forces the movie to become a sort of abstraction from reality. In some way, it's easier for the audience to accept it because they see real people moving around in a lifelike environment. When a movie leaves things unsaid, it lets the viewer imagine and auto complete the characters. But when you think about what the movie explicitly depicts, most characters revolve around a single gimmick.
On the opposite spectrum, a novel writer uses an abstract medium to convey the illusion of realism. Everything unsaid simply doesn't exist. If the surroundings aren't described, then the scene is in a blank liminal room.
Writers have little benefit from reducing abstract text into another abstraction of reality. Instead, they need to allocate more resources into portraying a consistent and immersive realism. Thus writers spend a lot of time convincing that their characters aren't just imaginary mouthpieces, but actual people who could exist in another world.
I think this is especially important for wish-fulfillment novels, where the reader wants to identify with realistic flawed people rather than singular embodiment of a philosophical concept. Novel characters must be shown to flounder on their way or have a wandering mind towards their interests.
In conclusion, screenwriters work from reality towards abstraction, but novel writers work from abstraction to reality. This can affect the methodical approach to design plots and characters at a fundamental level. I think this discrepancy can be felt in adaptations between books and movies. Even 1:1 novel->movie adaptations end up weird or strangely bad. 1:1 movie->novel adptation can't even exist, writers have to pull shit out from their ass