Business books are entertainment, not strategic tools

I am always amazed how most business book authors take a simple idea that could be described in one page, and turn it into a 200+ page book with popularizing narrative. What's more amazing is that the ideas are usually commonsense, but due to human nature are seldom practiced.

Doesn't that describe most good ideas in life? Things that are commonsense (especially after the fact), simple, seldomly well practiced because of human nature, and can be communicated in a few paragraphs but take years to understand?

Kindness, democracy, business, performance in sport, scientific method etc.

I don't know one good idea that can't be communicated in a page or less.

Why do you think it is not possible?

Of course it is hard work to distill something complex, but I have some naive intuition that it would actually be possible.