"At the Library of Congress, I was asked why there are so many significant Canadian SF writers, and I’ll repeat the answer I gave there. Canadian socialized medicine means that many of us were able to become full-timers at younger ages; I’ve been a full-time freelance writer since 1983, the year I turned 23. So, one perhaps sees Canadians doing better, more important work earlier in their careers, and being more prolific, as well, because they can devote full-time efforts to it, rather than having to be shackled to a a nine-to-five just so they and their kids will get to see a doctor routinely."
There's probably some truth to it, but it doesn't address the question of writers in general, not just in our genre. Has anyone studied whether there are more full time Canadian than U.S. writers per capita? I wonder if they have. It's an interesting question.
But I also wonder if some of it has to do with how long winter lasts? If you're not fond of the cold, you just stay inside and write.