well, if one keeps an open mind, they 'may' actually learn something from debates about taste. They may not choose to change much, but they may at least see that there are other ways to go..(it's hard to 'show' people how to tell a joke better, or to explain exactly why this song is elegantly funny, while that one is sorta juvenile and shallow.)

'Taste' is sometimes a matter of habit...sometimes a matter of culture...and sometimes a matter of actual genetic difference in how the brain is wired. We can alter some of these with slow education, but seldom by just informing someone that "mine is better".