Publishers and booksellers refuse to publish more conservative books, for instance many independent bookstores reportedly refuse to publish Cameron's autobiography

He argues that the industry’s “definition of pluralism can often be narrow and metropolitan” – while publishers have largely recognised the need to increase racial diversity in the industry, attitudes towards political diversity are more complicated. “There are certain kinds of narratives that most of the industry is reluctant to publish and promote.” Mundy says he has noticed a difference between two visions of liberalism within publishing: “There’s an older generation of commissioning editors who are more inclined to take the view that any argument can be valuable, as long as it is interesting, well expressed and adheres to basic values of tolerance and decency. Many younger editors are more passionate about contemporary political struggles and take a narrower view about what they and their colleagues should publish.”

Also https://www.thebookseller.com/news/indie-booksellers-split-david-cameron-memoir-1078736

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