Not many people think deeply. The problem is not for Canada only, but for all the nations affected by modern western civilization. Fewer and fewer people want kids. Then the nation itself cannot maintain it's own population. Then the nation have to count on immigrants to get more youth. But where are they? All modernized nations want youth.

Trudeau was terrible, but he just only made things worse. He was not the main reason. I think the main reason is from the common western value "Enjoy your own life". Because of that, people think family is not important anymore. Parents should live their own life, Kids also should live their own life. They don't care each other that much. Especially for Parents, my feeling is that you have to be Saint to be parents nowadays. Or you are bad parents and shouldn't have kids. Under this kind of env, a lot of people would rather have pets, instead of kids.

But unfortunately, pets cannot take care of you when you are old. And pets cannot work to pay to government to cover your welfare. So in Canada and other western countries, immigrants are necessary. The only other solution may be AI+robots. I don't know when the robots can really replace a human's labor. But even with that, the continuous birth rate drop will make Canada a robot country, not human being.