I got lenses which says -6.5. I have no idea what it really means.
But I apparently lived most of my childhood before the first degredation of my sight, and I know for a fact that if I can't get glasses or lenses, it will take me 1-2 days to adjust for normal life. After that, I will behave as if I have a almost normal vision.
Sure I can't read anything at normal distance, and I will have trouble reading the church clocks at 400m+, but those are very insignificant tasks compared to just how much I can use my poor vision once I get used to it.
After all, my favorite hobby as a child was reading. With my awful eye sight. And I still read a lot, after getting classes, at a age of 11.
I don't think the amount of near or far sighted has changed at all over the last 100 years. I doubt it. What I think has happened, is that we give children glasses far too early, so that its very obvious that your sight is bad. Otherwise you would reach the age of 13-18, and maybe need some reading glasses.
Once you get used to having imperfect vision, you give no fucks about it. Its just something that is there, and unless you are used to wearing glasses, you don't really care.
You see the same with people starting to get older too. They only use glasses for reading, watching TV, or using a computer. Their vision has to degrade a lot before they feel forced to have driving glasses, even if their ability to read signs is technically poor long before they feel the need.
Remember: I doubt we have had real selective breeding for eye sight since we got the tech for pottery, walls, farming and breeding animals. I seriously doubt it. What gets wed out is those with too poor eye sight. And that is extreme levels of bad, its obscenely bad. You have trouble playing sports with such poor vision.
And on the top of that, reading being common is almost a thing of modern civilization, as far as we know it. 150 last years? 170? Its uncommon, from a evolutionary perspective.
You see the same once you go over modern medicine, and the degrees of treatment. Childhood mortality decreased severely? Such a amount of resources that babies born too early can be saved? Babies born sick can be saved? The later 2 cases are rare compared to the first. And third world countries would not go towards a "overpopulation" unless the basic medical treatment fixed most of the first issue.
