I will accept that the CBC *may* be left-wing if you accept that they have barely any editorial content - and that content is itself balanced. I can only recall Rex Murphy and Neil MacDonald opining there.
Their 'editorial content' is in their selective story coverage, how they tell those stories, and in how they treat different political views and parties. Witness Rosemary Barton's hardball interviews with Jagmeet Singh and Erin O'toole and then her fawning, softball questions to Justin Trudeau.