The original creator of the Forgotten Realms is Ed Greenwood who is a Canadian Librarian and Author and for those who knew what to look for the Forgotten Realms is infused with Canadianess. This makes it distinct in a way from all the American created settings. Which is not to say that FR doesn't have some American influences, it does, or that the Canadian influence strong in every part of FR, but it's a very Canadian setting at heart.
You see it in the environmental descriptions and the way heart urban centres are weaved together with vast and I mean vast regions of nature and rural farming regions, the fact that most of the races and cultures of FR are in fact immigrates to the world.
You see it in the fact that around the great cities of the Swordcoast you Native American like Tribes of Uthgardt.
You see it in the Parliamentary Democracy of Turmish.
You see it in the farm communities of the Dales.
You see it in the Law and Good government ideals of Cormyr.
You see it in the two solitudes of Aglarond and its history.
You see the era of Hudson's Bay (a corporation that ruled most of what would become Canada before Canada bought the land from them) in Merchant Ruled nations like Sembia and Amn.
You see it in the multiculturalism of the setting, the greater comfort with diverse forms of sexuality in the setting, and so on.
Ed Greenwood was the biggest Canadian influence on FR, but he is not the only one, Bioware which made the BG games was also Canadian and there possibly others.
Thoughts?
So I'm Canadian too, and I have never once thought of FR as Canadian. Sure there are commonalities, but these are likely more accidental than anything purposeful.
The urban vs rural sprawl is a pretty common thing in Medieval Europe, which FR seems to be inspired by more than modern Canada.
The tribes of Ulthgardt have much in common with Native Americans as well as those in Canada (I find it interesting in your OP you used that term instead of the Canadian term Indigenous Peoples).
Parliamentary Democracies are not unique to Canada, and of course originated in England.
Farming isn't unique to Canada, not sure why I need to even point this out.
Aglarond isn't the two solitudes, it's one culture ruling a different one. That's not really what the solitudes was, and is a pretty common thing in many regions throughout history.
The merchant nations have more in common with the British East India trading company than they do with the Hudson's Bay one, if you look at the exoticism of those merchant nations.
Multiculturalism is not unique to Canada (the US, UK, Australia, France), and regions of Canada like Saskatchewan, Manitoba and Alberta are not really that diverse, especially outside of the urban centers.
My larger point here isn't that you're exactly wrong; if you look hard enough and squint you can find similarities between aspects of FR and Canada. However, if we actually look back and try to devise Ed Greenwood's actual creation of FR, do I think we was pulling from Canadian influences? IMO, I really doubt it. More likely he pulled from several different societies from across history, like most good world-creators.