I've also kept short notes for years, with a dozen or more engagement calendars on my bookshelf. What brought this on, for me, was realizing that so many rides aren't worth posting in the "How was your commute?" thread. I think I did post about the self-tapping fender washer + bolt combination flatting my tire pre-pandemic, but I can remember that one fine. It strikes me as a bit strange that I tell people I ride for my health, my finances, but mostly because I enjoy it; but without notes I'd have a hard time telling you about last week's rides.
Of course (and off topic), this is precisely why I tell people going on tours to take notes, whether in a paper notebook, or a blog, or a series of emails. It's too easy to forget otherwise, but pegging those memories lets you review and remember many years later!