Journals can also be electively subjective. Yes, a photo can be framed or posed, but it's harder to edit awkward truths out of a photo rather than omitting them from a journal.
So if I really want to, I can find out how I was generally feeling in, say, 2006, and what sort of questions were on my mind and what ideas I had. Usually the answers are: pretty much the same, and stupid ones, kind of like today but worse. So it turns out that I don't want to review my journal much. But I only know that I don't want to because I have the option, so it has a reassuring function, and writing helps me think in the first place.
When it comes to photos, though, I'm with Ray Davies:
People take pictures of the Summer
Just in case someone thought they had missed it
And to prove that it really existed
People take pictures of each other
Just to prove that they really existed
Don't show me no more, please
Yet many people seem to have the time to sink in endless time on Netflix, FB, Insta, candycrush or doomscrolling somewhere else.
( I have no data and I made this up)