[NegatioN]

There seems to be a focus on something about the brain "calcifying" or people getting stuck in their own pattern over time here.

That may be a component, but I think anothet thing that correlates heavily with the graphs presented in the article is simply: When you have enough spare time to prioritize music. (although you could explicitly prioritize it like some commenters mention)

I still find lots of new music, but it always comes in periods of my life when I have some leeway, and those are fewer and farther between now.