we must always keep in mind that what we value will not always mirror what others value

I think that's a separate issue, to be honest. The division I'm talking about is really one between (a) things in favour of whose quality someone can present a rational, coherent argument and (b) things about which people can only say "I like it". Of course there are a few transcendent works of art whose effect is such that it's difficult to think beyond response (b), but in general I assume you'll see the distinction I'm pointing at.