You don't think it's "As good as it used to be" because you have no sentimental attachment to the music that is being released today.
It's been written about hundreds of times. The music of our youth makes us think of our youth. You attach the music to a simpler time. You have no fondness to today's music, even if it's in a similar genre to what you used to listen to, because as you get older you don't relate it to life events like you did when you were younger.
So you don't even bother to seek out anything new, because you rather the comfort of your "youth music" and how it makes you feel.