you are richer so you can afford thicker copper

240 everything, lfg. Every outlet needs a hasher.

Old standards and safety concerns probably.

It is probably legacy. What’s interesting to me is that we (US) at least have a 1:2 voltage ratio to Europe/Asia. So transformers can easily convert between the two systems 120-240 V or vice versa. It could be worse if the ratio was something uneven.

Safer

If I remember right it's because early lightbulbs filaments couldn't take higher voltages, and by the time better lightbulb filaments were used so much of the country was already on 240v split to 120v they decided it was too expensive to fix it.

North America doesn't make sense as a whole.

In the development of energy the 120V came first and first nations or cities used only 120V. The 220V came after. Here in Brasil some cities have both, but some only 220V.

What I dont understand is the frequency. In Europe is 50Hz and we 60Hz