What would change if 90% of the world was ambidextrous, with 5% being left handed and 5% being right handed?
How would you go about forcing kids to write with both hands in schools in the early 1900's?
Good question lol, you can technically learn, but it is incredibly difficult to be truly ambidextrous; in the 1900s I can imagine there being some kind of hack pseudo-psychiatric institution popping up designed to teach these "disabled" kids, however if this is prevalent in 10% of people, having a dominant hand would become culturally acceptable earlier than most other conditions, and special tools might be made to allow these people to easier function in society.
I don't think having dominant-handed tools would be as important as having left-handed tools is today. The other hand is still usable, so whatever tool someone with two dominant hands can use could probably still be used by someone with one dominant hand.
Actually that is a good point, I'd have to agree here.
I’d wager it’d have impacts on tool creation, premodern warfare, and perhaps some different notions on philosophy and language. I dunno if I’m smart enough to parse it out all the follow on effects, because changing any of those things creates massive butterfly effects.
Ignoring the fact that would mean we never learnt to walk upright
It is very unlikely anyone has a dominant hand without it. Left handed people hold at small percentage because it is basically cheating
The brain is less separated, and so more strongly interconnected. That aids in several complex tasks like Speech
The other advantage. People don’t expect a left hook. Most people hit with their right hand first. An attack from the left is unexpected. It is harder and more difficult to react to a left handed person
That advantage wanes if too many people have it, and doing complex tasks better is not a good trade of if you are doing all simple tasks worse (ask people who uses computers)
So. Yeah. If we are ambidextrous. No one favours one hand over the other
Nothing significant besides being right/left handed would be seen as a disability