Few are loudmouths on social media, but there are more in expat social gatherings, complaining about just about everything that is different in their new host country.
Canadians however, seem to really work to fit in. Almost all I met learned the language, participated in cultural events and made local friends.
they also do not mingle with locals. Even in the South of France I knew many Brits who did all their shopping at the "British groceries" store to buy "Australian wine" and they generally do not welcome non-native speakers or much preferably also Brit (note native speaker to the colonialist always means the person does not speak another second language - e.g. Indians will never be "expats" in their eyes)
Have seen many Australians, Kiwis, Canadians who actively tried to avoid that specific expat crowd, but Brits/Americans (or also Japanese) are _very_ rare to mix with locals outside their work environment.
It doesn't mean they're bad people. I have many friends who would never bother to go abroad unless it's a 5-star wellness trip isolated away from all the reality (and locals) of the country. They're just not the most interesting or adventurous people and so it's OK if they stay in their own little bubbles without bothering the rest of us imo :)
Usually if I hear my mother tongue in a foreign country I usually change to the other side of the street.
I'm also an expat/immigrant. I met some people who have been living here for 10 years and haven't picked up the language yet. The only reason I know about them is because they heard me speaking another language in a quick phone call and wanted a friend.
Like parent said, nothing wrong with that (plus, I'm not American, so I can't speak about the problems mentioned by the GP post)
It was a brusque move, but, in retrospect, who needs that sort of mess?