@Charles I have always worn over-the-calf socks because they stay up—they don’t end up bunched up around my ankles. The only way to make shorter socks stay up is to put a circulation strangling elastic top in them, or equip them with vertical stiffener ribs. Neither of these solutions yield comfortable socks.
The reason sock length, and all other elements of clothing design, move from cool to uncool and then back again has nothing to do with comfort of what really makes sense. It has everything to do with convincing gullible consumers that the clothes they bought last year, and that will be perfectly serviceable for many years to come, are suddenly uncool and must be tossed in the trash and replaced with the new, cool kind.