There's no prestige or significant Chinese communities in other cities besides Toronto and Vancouver.  Wealthy Chinese buyers are looking for large Chinese (from China) communities where they can get by speaking only Mandarin, shop, conduct business, make friends, eat at good authentic Chinese restaurants.  Toronto and Vancouver are places where that can and does happen.  People writing these articles don't know much about mainland Chinese it seems.  (BTW I'm Chinese.)
A lot of these articles focus on Chinese buyers but completely ignore the Persian buyers and builders of which there are many in my neighbourhood in Toronto.  Numerous houses are being bought and rebuilt by Persians who come with loads of money.  Why is there no mention of them?