Mostly the living authors who have left the worst taste in my mouth with their personal/interpersonal behavior have not been able to keep that from their books. When the text is warped way far away from the storyline just in order to say how awesome Author's Viewpoint is and how much Thinly Disguised Opponents suck, it's a lot easier to sigh and shake my head and walk away.

Not that the world is free of problematic counterexamples, of course, but "disagree with" and "leave bad taste in my mouth" are somewhat different for me.