////I make my living by playing and singing and teaching////

So does my bass instructor and he says that I am BY FAR his most musically astute student. He can mention any artist or song and I know it. Usually, I have that song and that artist somewhere in my collection. Although he's teaching me double bass, I have played bass guitar for decades. When I played one his bass guitars, he was impressed that I had my own style but that he could hear so many other bass guitarists in my style. He complained that too many bass guitarists today sound like Jaco Pastorius. Now there's nothing wrong with Jaco but there's more to bass guitar than him. When I look for an influence to improvise my way through a passage, I have so many to choose from because I've listened to so many. These other guys have only Jaco to reference so guess who they sound like?

So I hope as a teacher, you are teaching your students songs and techniques by people other than the ones they listen to. It's YOUR job as a teacher to make them aware of new things. If you don't do that then, sorry, you're not teaching.

No, you don't tell them that what they like is bad. Who does that? But you open them up, expose them to more than they were ever aware of. Otherwise, they are not learning anything.

Frankly, I'm afraid Americans don't do that anymore. They have the Will Fly attitude: "Oh, just let them listen to whatever they want. It's not my job to teach them anything about music." Fine attitude for a teacher but it's not surprising.