I’ve wondered that myself. Afaik, there’s no real information about historical vision acuity beyond the extreme end where it amounts to being blind.
I have to think that some percentage of people had vision deficits that were bad enough to need glasses and from there up to being not-quite-blind. I know that we hover around 20+ percent of the world population being myopic nowadays. If it was even half that for millennia, how could that not influence damn near everything?