Even if two people with cultivated tastes don't agree on everything (or anything), their opinions on say movies or music are worth more than some guy's who just "likes what he likes" and never really got into exploring that space any deeper.
I was responding to your tl;dr not the GPs point. I think people who love Citizen Kane should encourage other people to try it, and people who love Parasite should encourage other people to try it, and we shouldn't make broad pre-judgements like "because you are younger than X years you won't like this movie that's more than Y years old." Obviously if we know someone else's particular taste we might be able to guess that they will strongly like or dislike a particular movie (e.g. my mom dislikes any violence, she would hate Parasite).
