Is it unpopular? I grew up in Alberta and know many people who would be happy to separate, going back to my step dad way back in the 90s. Plenty of Albertans also still hold a grudge for the National Energy Program[1] that bankrupted them in the 80s. At the very least, many Albertan's perceive Queubec separatism as a negotiating tactic that allowed Quebec to secure preferential treatment from Ottawa and would be willing to try the same approach.
[1] https://en.wikipedia.org/wiki/National_Energy_Program