Hard to say. The separatist demographic is definitely becoming old men shouting at clouds. But up until the last election with the big NDP surge, the BQ was a coalition of separatists, Quebec-first people (who don't necessarily want to separate, just have an adversarial relationship with the federal government and want their representative to be emphatically pushing for recognition of Quebec's special status and interests), and socialists who hitched their wagon to the BQ because they had more federal power than the NDP.

So the question is how much of the shift in support in Quebec to the NDP is permanent, and how much will shift back to the BQ in upcoming elections.