Foreigners will come to America only if they can get a green card. Would you buy in a country where you can’t be guaranteed residency much less a tourist visa?
I have friends overseas who don’t even want to visit America because it’s too much of a hassle. First you have to pay non-refundable $100 with your visa application with no guaranteed of being granted the visa. Then you have to come back for the interview. To them, the hassle is not worth a holiday in America.
EU and Japanese citizens can come to America without a tourist visa but they have to apply for residency.
I agree with your comments about Vancouver, one of my favorite cities. In the 1990s you could get a house for $200k in Vancouver and many Hong Kongers bought there because with their money, they could get residency and eventually citizenship (they needed a safe haven when HK was returned to China). I’m not sure of the exact details but if you bring $100k into Canada, you can get residency. In America you need $1 million plus create 10 new jobs (they have inspections to verify that). That means that you have to open up and operate a business. You can’t invest in passive income businesses such real estate or the stock market.
