He makes some valid points about every generation predictably denigrating the music produced by the next.
But the stuff about your musical tastes being set when you're a teenager is complete BS.
In my teens I was listening pretty much exclusively to heavy metal bands like Maiden, Megadeth and Anthrax. I stopped listening to that stuff in my early twenties. It would never occur to me to put one of their albums on these days.
Now I mainly listen to to soul, funk and jazz stuff that I would have turned off if it had come on the radio when when I was kid.
I'd guess most people are the same, eventually we get bored of the same old, same old and move on to something else.