It’s not because it makes you classier: it’s just that it gives you the capacity to better appreciate more kinds of music (and, I’d argue, some other forms of art) *if you want to* than you would be capable of managing absent this basic grounding. As for instrument-learning: it’s just the quickest route to literacy. I took a music appreciation class in school with kids who didn’t play anything: the teacher was stuck pretty much only ever discussing song lyrics. (Anything else would have been gibberish to most students.)