Good literature is more like good code (someone who knows about programming can tell it from bad code) than like brace style (a mostly random choice).

I think the idea that art/literature is "ridiculously subjective" is mostly on the west side of the Atlantic. In ole Europe we tend to take our literary canon seriously, and don't think that all taste is equally OK. Of course individual readers and critics might prefer X over Y, but the value of great works and authors is not doubted in aggregate.

E.g just because some people like Bieber and others like Mingus, doesn't make Bieber as just good as Mingus. Music/literature/etc is a craft (in which one can tell a good from a bad practicer, even if he is not "into" the final artifact) rather than something like different ice cream flavors.