I have no formal education in the field, no serious interest in it and no deep knowledge of it either and I'm very well aware of it so you can't wonder that my interpretation of the various theories is unorthodox and maybe even plain contradictory to the scholarly approach. Nevertheless, the amount of actual experts that participate in their respective threads on this forum is negligible (debates over economics or politics being prime examples) so I weighed in this one, something I wouldn't dare to try if confronted with a debate between art theorists. I would just sit and learn from their words then, just like I did with your post.
However, if we delve into the expressionist approach again for instance, I wouldn't disregard Cage's intent to express his inner thoughts when he composed 4'33". If I quote the same part again "Until I die there will be sounds. And they will continue following my death. One need not fear about the future of music." Everytime 4'33" is performed, the audience can hear for themselves that indeed the future of music is ensured by the omnipresence of sounds, basically being confronted with the thoughts Cage had in the anechoic chamber. Yes, it is not the prime point of the composition but I say it is there.
One of the reasons why I listed several theories shallowly instead of one deeply is that I preffer Babylonian thinking, damning strict adherence to certain methodology and embracing whatever interesting knowledge can be obtained from synthesis between them. To give an example from economics, I believe both sides of the Methodenstreit were wrong and could progress better if learning from other's strengths. Yeah, many theoretically inclined academics hate such lack of commitment to one method but that's how I roll.
I figure that one can't deal with the question "what is good and what bad art" without touching the question "what is art". I believe in inductive approach to the latter question, we first start from the canon art and then try to form an answer, not invent the definition of art and sort things according to it. If you excuse little argumentum ad verecundiam, 4'33" was recognized as musical composition by the people more knowledgeable than me in these matters.
Also, I didn't hint at Draugnar's stance to the problem of 4'33" but to his overall approach in that last post. It really is pointless to use smug comments that are objectively untrue in a serious debate. I don't object to usage of smug comments, they are fun and whatnot, but they should be in line with one's behaviour. Since he took the issue seriously before, this change in approach signalized that the whole exchange of ideas would be pointless from then on.