This isn't a completely sufficient argument, though. Surely, any person into an artform will at some point be able to recognize the difference between what is g

This isn't a completely sufficient argument, though. Surely, any person into an artform will at some point be able to recognize the difference between what is good because it is good and what is good because it is different. A good critic would be able to differentiate these two things and give a review with some nuance, but it seems incomplete to say that the critic problem is mostly the fault of seeing way too much junk. Anybody who is actually in to anything has seen a ton of junk, but not everybody has lost their ability to clearly judge things.