Free markets are extremely effective in many contexts, but they have major blind spots. In a few critically important domains, the profit incentive does not align with society's will. Take healthcare for example. Private health systems shut out the poor. That doesn't mean poor people want to die. It just means they can't afford what the doctor is asking. In just societies – places like Canada – the prevailing view is that everyone has a fundamental right to quality medical care. That's how we got a public system which provides the universal access Canadians want in a way that private healthcare never could.
Public broadcasting is a public institution that helps society compensate for the market's inherent weaknesses, just like public healthcare and public education do. Private broadcasters have an incentive to spend as little as they can on Canadian programs, since it is more profitable to re-transmit popular shows from the US. Private broadcasters serve advertisers, and when these powerful companies become the subject of political debate, private broadcasters face a conflict between reporting the news and serving their clients.
Canadians want and deserve Canadian programming that helps our society develop. We also deserve fully independent news that puts citizens first, not shareholders or advertisers. And that's exactly what public broadcasting does.