Myself I believe the opposite. The brain itself is one of the most powerful filters that exists, and it attempts to be lazy and fill things in and compresses away the common. All that time we're not doing anything novel just gets compressed away to almost nothing. When you're a kid and seeing new things, feeling new things, learning new things you can't compress that away.

I'm only middle age, and this has been the scariest part. Feeling older is hard. But watching it go faster is harder still. like you can more directly see all that is left.

Although part of me thinks some of this is from being substantially busier than ever (work + kids), and hoping maybe it can slow down again, at least a little bit.

Novel experiences take up more processing power and are burned into memory so they're experienced at a slower rate. That's how I understand it anyway.

It's coherent. More newness => more memories per period ~ slower to go through. Less newness => less memories ~ nothing to go through (faster sense of time)

Boring feels slower in the moment, but quicker in hindsight. The minute might be a slog, but the years still fly by.