That's easy.
The copyright owners in Canada today are putting our pure garbage. People just buy it because in a lot of cases, they have no choice.
If the market was opened to the world, the Canadian TV shows would be exposed for the 3rd rate crap they are. The people who used to have no choices, could then bail out, causing a "reduction in opporunity"
Plus the Liberals can't stand the thought of not being able to control what everyone reads/hears/watches. It's just their nature.
about 1/3 to 1/2 of the first run television programs on the tube are Canadian produced (including #1 rated "CSI"). Crap, indeed.