Hello is not a made up word, it’s a variant of hallo which comes from middle German and a hatful of other places according to Wiki.
I don’t know why people complain about American English replacing British English. American English IS British English, really. The number of differences words really is tiny, and even then it’s only a few simple substitutions with words which are just used somewhat less frequently. Given how much the cultures have diverged since the 17th century I think it’s amazing how consistent they are.
If someone posted on here in Scots, most English would have to read it pretty carefully and still might not catch on. I hear a lot of people complaining about not being able to understand Geordies or Glaswegians. And yet we understand Americans perfectly, and when they post on here it’s generally undetectable. They have to identify themselves.
30 of your Britishisms used by Americans
Er, their entire language is a Britishism!