Yes, definitely; it's a deterrence. When a Chinese official is about to violate or torture a Tibetan or a Uighur or a Hong Kongese, they will think twice and say, hey, if my son or daughter has to study in Canada or America, I had better not torture, because my visa could be denied. Canadian journalists who come and investigate this issue could also report on it.
Otherwise, they're acting with impunity. This is a small deterrence, but nonetheless a necessary one.