I don't know that the marketing of the Canadian players is an issue. I was curious why someone would be hesitant to bring in a Canadian player, especially one who is playing in the US right now under one of the top coaches in the country, at any level. If they were coming from a Canadian university or a professional league up there then I could understand the caution but that's not the case here. I do think that most of the recent Canadian players seem to be a bit soft and lack a strong competitive drive but I don't know if that comes from being Canadian or not. When I say that I mean players like Wiggins, Bennett, and SGA but I think it might just be limited to those players specifically. I found a list of Canadian pro's and there are a number of them that don't have that problem like Cory Joseph, Kelly Olynyk, and Jamal Murray.
Here's the list I found if anyone cares to look at it. I didn't know some of those guys were Canadian either, like Joseph and Olynyk, so I'm not sure their marketing of their players is much more of an issue than some of the hype that follows other foreign prospects like Dante Exum from Australia or Doncic from Solvenia.
https://en.wikipedia.org/wiki/List_of_Canadians_in_the_National_Basketball_Association