I can, sadly, relate to this. Is there a name for this phenomenon or is it simply a trick of the mind, a calcification of temporal perception that gradually boils the frog until one day you realize that referencing Van Halen or Max Headroom results in blank stares?

No, it's not! I was there! It was 46 years ago. How did that happen? I can't understand it.

When I was a kid in the 1960s, World War 2 was ancient history, but at the time, it was only 20 years ago. And now, 20 years ago is only yesterday.