Pressed to put it in a nutshell, they reply that neither system has abundantly clear advantages over the other. If you lose your job, there is a high probability that you'll find another one. It just won't necessarily be the job they're in right now. The political left and the union movement in Canada wouldn't trust that sort of promise all that much, he warrants. In Sweden, it's the unions who came up with the idea and sometimes pushed it onto management.
Swedes view job flexibility as an opportunity to gain new skills, for instance.
Canadians, hardened by decades of more brittle relations with their employers, are apt to be more suspicious of the concept. In Canada, unions on the whole are not terribly interested in encouraging flexibility. In fact, quite the contrary. The impulse is to regulate these as much as possible. As a consequence, there is less room to manoeuvre.