I know what you mean, but I put it down to people new to the internet. They often are bad at typing so take shortcuts like 'u', and they've never written before

I know what you mean, but I put it down to people new to the internet. They often are bad at typing so take shortcuts like 'u', and they've never written before as much as one does online. Within a year or two there's definite improvement in my experience; practice with touch typing and with composing text. Country has nothing to do with it IMO, except that the US rarely sees people in their 20s discovering the internet for the first time.