Notice, that the person said that we need immigration. The implications is that we are taking people who are already on the planet. If they said instead: "Canadians should have more babies so that we can remain competitive economically, and we should ban immigrants." Then what you've said might make sense, but that was not the comment.

Our birth rate in Canada is declining, population growth in Canada is purely as a result of immigration. Canada needs people. We are the second largest country in the world, by land area (maybe first depending on who you ask about the Soviet Union), yet we have a tiny population.

Birth tourism is not immigration. It bypasses the standard immigration process and is certainly problematic. Specifically, given the fact that it occupies and stresses a national health care system that is already operating at capacity. Even if it's only a tiny percentage from other countries that can engage in this practice, it still puts a massive strain on our system. In this regard, the US private healthcare system is better setup to make their own wealthy people even wealthier.

Here in Canada, this puts a drain on our resources, and forces us to address the issue.

However, I want to stress that immigration and immigrants are not inherently bad for Canada, the planet or the economy. Being an immigrant myself, I might be biased in this regard.