This could just be a feature of getting good things when we give the NDP a larger share of power than usual, though. The Liberals didn't want universal healthcare, it was a concession given to the NDP because they had to. But it's not like a majority NDP situation at the time wouldn't have passed it.
Much the same as dental care today. What exactly are the Liberals bringing to the table other than acting as gatekeepers making sure the system isn't as expansive as it could be?