My partner says the American tourists are like special children from a special school who need supervision. They are easy to pick for many reasons, but mostly because they look unwell and fat, like they are young but 80. They are not used to walking, so they usually stick to the centre of a city, have to be in groups with a guide who has a flag and talks to them like a school excursion. By 2pm they are all tired and take up many of the restaurant chairs and talk absolute shit loudly. When this happens, everyone is annoyed or leaves the area for better things.
It seems all other nations, not just European, you can find them everywhere. They are used to walking and confident to explore, discover, and do things by themselves as normal adults. I would love to see average step count and food intake comparing different countries.
Where the English are different, they just look unwell, but are usually fit and confident. I do not know why this is, but I think it's just they are pale so maybe don't do many outdoor things at home. But many of them are not and you could confuse them as German, French, Dutch, etc from afar.
My favourite is Australian and Canadian. They are very adventurous but polite and shy until you get to talk to one, then they're loud, excited, and funny. They always look lost but never are. It's weird. A wild Canadian or Australian can appear in the most obscure places. Canadians are my favourite tourist to meet at the snow. So friendly and up for anything.