I think the case you make for the art can be surprisingly rue but I think at an individual level.
I can say this for Literature and food. With books, when I read one I can not only remember the book itself but the surrounding incidences - like what time of the day I read it in, who disturbed me when I was reading, did I leave the story in middle and go to sleep or I powered through the drowsiness but mostly what was my state of mind throughout the story. It's like a one long mnemonic function for me.
I wish I had your memory! I don't think improving memory or assisting memory is a primary function of art, and such an idea doesn't grab my attention. But art's function of recording what the artist feels towards something is at least worth considering. What really captured me was the potential value in allocating attention to detail towards areas of interest in the artwork as per the artist's discretion. I don't believe the author was making the claim that art aims toward assisting its viewers to remember their own day-to-day experiences in an objective way, per se. I believe the author was proposing the possibility that many artists approach their work by bringing in a great amount of detail or visual interest to the important and memorable elements of their composition.
Thanks for your point of view!