>We have glasses because modern society requires focusing on close objects like books and screens causing eye strain.
This doesn't make sense. This only explains why people use reading glasses or bifocals over the age of 40.
Most people needing vision correction are near-sighted (myopia), not far-sighted (hyperopia). We have glasses because we need to be able to see things and read signs at distances greater than our arm reach.
There's something else going on causing SO many people to need vision correction.
>Cars are great for modern society
As someone who lives in a walkable city with excellent public transit, I completely disagree. Cars are a disaster and a cancer on society.
>While i doubt its the only factor, diets higher in sugar than what hunter/gathers would have eaten seems plausibly linked to there being more cavities in modern times.
I think this is a big thing, though I think it's more complicated because some people eat plenty of sugar and still don't have cavities, so I think sugar affects different peoples' bacteria differently, or different people have someone acquired or evolved different bacteria that respond differently to sugars. But yeah, sugar seems to be a central issue.