That novelty point is the one that holds up best in the literature I've read. William James wrote about it actually, he called it the "telegraphic" quality of adult memory versus the "copious" quality of childhood. Children encode everything because everything is new. At some point you stop doing that and years just... condense. I retired two years ago and somehow that's both the longest and shortest two years of my life. Depends on how I think about it.
I turned 31 last month and genuinely could not account for the last two years. Like, what happened. There's something about the ratio theory that gets me. Each year is a smaller fraction of your life so it compresses. Doesn't make it less unsettling.
my patients who are in their 70s and 80s say the same thing every time. something about novelty, your brain stops encoding new memories as carefully when everything becomes familiar. i don't know if that's comforting or not