You shouldn't feel you're a failure. Be happy he appreciates and is into music. I've accepted the fact that though our relationship with the band is I admit, different and special-- although my son and I have seen Rush perform about 18 times together, and Alex turned him on to a ton of cool music (when I told him-- it was meh...Alex tells him, he's a fan 😔), and he's into a bunch of his old man's music, he's still really into pop, and rap. I'm okay with that.
My mother sang opera at the Met before I was born, and my old man was only ever into country and bluegrass; but I was encouraged to find my own path. When I was five, I was into Motown, the beatles, and Beethoven.
For my sixth birthday, my mom bought me a steel drum; and three albums, "Bill Evans at the Montreux Jazz Festival", Pink Floyd- "TPaTGoD", and "Buddy Rich...The New One". I played the Hell out of those albums.
The point is, I fell in love with music of all types, and I've been into a ton of different genres at various stages my whole life. Be glad he's on his journey.
I will admit however, and I tell my kid...Most of the crap he's into, is horrible to me! 👎 but that's okay. ☺