Carney has taken a professional tone in comments regarding the US so far, being matter of fact and non-confrontational while still having clear boundaries. That is a good approach for communications with the US.
That said, him being positive about the call doesn't change the reality of how the relationship is transformed. Canada still needs to adapt to the new reality and pivot the economy away from US-dependence.
Just looking in on X today (yes, it's a toxic dump, but also where to look to see what the MAGA movement is publicly astroturfing), and I see #AlbertaSeparation and #CarneyWinsSecessionBegins are trending.
I think this is plausibly part of the plan. There are secessionist fringe groups in Alberta that are on-board with MAGA and will collaborate in a secessionist movement, and that movement is likely to get serious right after the federal elections. It will begin with an astroturfed move to deny the legitimacy of the election and to push for Alberta to separate. Saskatchewan will likely be targeted in the same way.
The supporters will be fringe, but it will be pushed by American media like Fox, by X, by the Trump admin, and maybe by Danielle Smith. The goal will be to weaken and divide Canada. Maybe that leads to little green men crossing the border with support of local secessionist groups in future, once enough division has been fostered.