Earlier quoted context omitted.
Unlucky for the UK coffee shop that wouldn’t take my USD this morning I guess? Not quite sure what you’re trying to say, if a country doesn’t want to accept usd…they don’t have to
Except a $100 bill is likely accepted. I’ve been to developing countries that will accept local currency, dollars, and euros. I doubt they would accept any pounds, tethers, or other fake electronic currency.
In most cases e.g. a French tourist would be fine taking euros, but a British tourist can take pounds and not pay to convert to dollars or euros first.