To say the least, stating that stopping or delaying the Kinder Morgan pipeline would be holding the entire economy of Canada hostage is hyperbole. The oil sands contribute about 2% to Canada's GDP and only a portion of that production would pass through the Transmountain pipeline. Moreover, there are some doubts whether the pipeline is even economically viable, beyond the questions of its obvious ecological (and related economic) risks. (See, for example, https://www.desmog.ca/2016/10/07/robyn-allan-qa-trudeau-government-dangerously-misled-kinder-morgan-pipeline)

The people of BC obviously have a say in whether this pipeline will go ahead, particularly since they are the ones who will have to live with any disastrous consequences it may have. Moreover, the pipeline will cross over the lands of many unceded First Nations lands. Whatever Notley might want to say, this pipeline is not a done deal.