The only reason Vancouver is on the list is stated clearly - healthcare costs. However, what the article DOESN'T say is that immigration to British Columbia is pretty much closed to the average person. My MIL's family, close to 200 of them, live in Vancouver/Richmond. She always thought she could go live with them in her old age. However, we discovered that BC now requires $350K cash - yes, cash - and you must declare your intent to start a business. They want entrepreneurs only.
You are, interestingly enough, welcome to be an 'illegal alien.' There is a six month max residency for visitors, but Customs honestly told us they don't enforce it. This means you can use their healthcare services, but you will pay for it with your own $$$. It is very inexpensive for regular day-to-day care. But getting specialists, especially for certain conditions, can be an issue. Even American $$$ don't always get you to the head of the line, then.
I don't think we should be surprised that Guatemala is praised for its beauty yet has immigrants looking to leave. I married an immigrant and they firmly believe the US remains the land of opportunity. South America lacks a stable middle class and corruption is rampant. Like Asia it is very class-conscious. As an American with even a basic SocSec check, one is able to live an upper-class lifestyle with ease because the currency exchange works heavily in your favor.
We have friends who had to go to Panama to live because he lost his job and simply could not afford to retire in the US. Fortunately his wife grew up in S.A. and speaks fluent Spanish. They took about 2 yrs to complete their permanent move - it was not an easy process. They also were smart to try to a number of different places by renting. They are very happy in Boquete where they currently live.
As we live in one of the most beautiful areas in the world - the San Francisco Bay Area, where people come from all over the world just to spend a few days here - we have no particular desire to live elsewhere or even travel abroad at this point. We've spent the last five years traveling a circuit around Northern CA, with occasional trips elsewhere (all along the West Coast; the Southwest; the Connecticut/Massachusetts area on the East Coast where I have relatives).
It has been terrific to be able to spend uninterrupted days in places we could only visit by day-trips when we were still working. We are foodies so this is another reason why this is such a great area to spend our time in. We do regular driving trips to Napa and Sonoma counties (separately; Sonoma is very large), Monterey/Carmel, Mendocino and the Northern Coast. Sooooo gorgeous!
We enjoy living in the city. We prefer the easy availability and wide variety of services, as well as having our HMO doctor/hospital less than 10 min. from our home. Great weather, beautiful area, staggering number of activities for every interest, varied social life, amazing food...can't think of anything we're missing.