As a longtime musician myself, I can certainly tell when someone is making mistakes. in one example, i've listened to so many versions of beethoven opus 111 that i've noticed a world-famous pianist who played the bass line in a single measure differently than what was written (sounded better his way, IMHO).

but what makes one "best" is highly subjective. i'm not sure what the research proves other than perhaps it's harder to move on from adolescent disappointments than is commonly acknowledged.

A more relevant question for the snob factor is "how do critics recognize when NEW music is great, average or crap." because that's pretty much what wine is - a constant cycle of new product, varying from year to year, even when it came from the same vines.

the valid "snob" angle here for both wine and music is that we aren't supposed to judge based on pure sensory experience. For example, a very sweet wine is going to be palatable to a lot of folks, but we're supposed to recognize the subtleties of a dry pinot noir instead. or compare most anything by john cage to anything by beethoven. or compare beethoven to justin timberlake.

there is a valid case to be made that once you learn to have "cultivated" tastes, you can pick out all these details and truly appreciate them. i once participated in a blind wine tasting where only one woman out of 30 people could reliably pick out the fancy wines from the cheap ones. for her, i expect the process of drinking wine is a lot different than for the rest of us yokels. Tasting things we can't notice, and appreciating them differently. good goal to aspire to, if we care, otherwise just admit we have no clue, be happy, and move on.