My friend said the same thing about cleaning out his garage last spring. He figured it was a Saturday job, but he was still finding old boxes of college textbooks in July. These small tasks always have hidden layers we don't see at first.
My uncle tried to clean his attic in a weekend and found five boxes of family photos he had to sort. Honestly, you have to set a timer for sorting each section or you'll get stuck looking at old stuff forever. I put on a podcast and just make a trash pile, a keep pile, and a donate pile right away. Tbh the hardest part is not reopening the memory box once you've already decided to toss it.