Not really the key point, but personally as a reader I have always disliked Chekhov's Gun. I like to believe in the world that is being described to me, as if it were real. In the real world, things just exist, they don't necessarily have purpose. So a gun can be described just because it's there, it's interesting, it catches the protagonist's eye, etc.

If I know the author follows Chekhov's Gun, then now I know something is going to happen with the gun, taking away surprise and suspense and possibility, and making the world feel much less real.