I don't altogether agree with this. For instance, it may well be that once you've seen Coma, you'll think (correctly in my view) that it's a vastly superior film to Extreme Measures. However, if you've never seen Coma, and in ignorance think Extreme Measures is terribly original, you would objectively be wrong, as Coma came up with the premise first.

Arguments about which film is superior are ultimately subjective, but only if one has seen both films. Calling one original and innovative in ignorance of the earlier work means the opinion is not informed. Therefore it is subject to hyperbole, exaggeration, and distortion. Therefore, it isn't objectively reasoned.

To your central idea, however, I agree that the notion of a guilty pleasure is absurd. People like what they like, and shouldn't be made to feel ashamed. I certainly don't. I only ever use the term guilty pleasure in jest, per my recent article. :)

I also do think that someone who has studied and understands screenwriting, direction, and so forth is in a better position to critique those elements. But obviously that doesn't mean a viewer can't still enjoy something such individuals consider poorly written/directed, etc. It happens all the time.