I tend to think of it more like this: There is a North American culture and then subcultures. "Canada" is in large part contiguous culturally with two North American cultural regions -- the midwest [hi there Minnesota, we love you!] and (at least parts of) New England.

This isn't really because of TV or cultural export but because of real population origins and movements. We say "pop" and have "Canadian raising" in our speech, and so do people from Minnesota or Wisconsin and that doesn't come from TV or radio or movies. It comes from being neighbours and descended from the same population groups. The border also used to be a lot more porous. My mother's mother were (German descendant) North Dakotans who just basically popped across the border and started farming and lived in Sask and Alberta... without a lot of legal hassle at all.

Overtop of that, yes, there is a whole set of other cultural/legal/economic overlays, and media is a big part of that.

But this is still a regional story-- there's I think more in common culturally between e.g. regular families in Ontario and Wisconsin than there is between Wisconsin and Florida.

From that perspective, I have rarely fallen back to Canadian nationalism. I would in fact have been more in favour of a stronger union between some US states and the US economy and Canada -- in the past. But events of the last year have made clear what many our Loyalist ancestors already tried to warn us about 200 years ago: there is a dark and frankly kind of insane undercurrent in American political culture, and the foundations of the Canadian state are anything but artificial, they are based on an entirely different perspective on governance and culture because there's something kinda messed up in the kernel of the American conception of governance.

Which I think the people of Minnesota are seeing right now.