Consider the brain as a giant recording device with very good compression based recognizing patterns from previous data. So the first time you eat an apple, it stores a lot of data because it's a new experience. The next time, it stores something more like "like the last apple, but a little more tart".
I think our perception of time (at the macro scale) is roughly a perception of how much new data our compression-oriented brain is storing. It's the sensation of accumulated novelty.
https://en.wikipedia.org/wiki/Entropy_(information_theory)?w...
So a monotonous 60 year existence is a fraction of the perceived duration of 60 years of a wild and adventurous, constantly reading, learning new languages, making new deep human connections - existence.