Did you watch the full video? He goes into detail.
I'm in manufacturing. There has definitely been a huge labor shortage and for the past couple of years hiring has been overwhelmingly immigrant. Mine is one of the only white faces in the plant, and let me tell you, they're paying the immigrants nothing.
The education angle is absolutely true, too. Education is almost free for citizens and incredibly expensive for immigrants and foreign students.
Also, it's worth pointing out that this thread called it the "Trump effect", which it obviously isn't. Trump played on xenophobia, demonizing immigrants, blaming them for lies he was making about crime, while Trudeau pointed to big business taking advantage of the process.
TLDR: Canada loosened immigration restrictions to meet labor demand and didn't tighten them fast enough when that demand passed, which they're doing now.