Its easier to form normal communities away from the city hellscape in the US.

While this is true in theory, the U.S also shares a southern border with Mexico. A country hellbent on sending not just their citizens, but the entirety of Central & South America as well to invade. And last month, we also saw Haitians are starting to make their way over as well.

I would argue Canada had the perfect combo of isolation + rural communities. For all of Canada's existence, it only had to share an undefended border with the U.S, who clearly wasn't hostile to them. If it weren't for the invention of the airplane, the country today could still have been majority white...