During last two year, MANY MANY doctors closed their clinics. MANY MANY nurses quit due to the workload and emotional toll. These folks already have some money and they do not want to enter the same rat race again. You need to replace them. Somehow. Getting young people is a good starting point. Getting needed talent is much better.
Now lets see some numbers.
1. Canada Deaths per year : 323000 for 2021-22 (
https://www.statista.com/statistics/443061/number-of-deaths-in-canada/)
2. Canada Births per year : 10.148 per 1000 people (
https://www.macrotrends.net/countries/CAN/canada/birth-rate) = 38,250,000 * 10.148/1000 = 388161.0
So only some 388161 - 323000 = 65161 in growth
For a country of 38 million and massive amount of land and natural resources if only some 65K are growing in one year, it needs fixing.
Because this does not even take into account people who want to retire or who can not work anymore.
This is why 500K is needed. To counteract this shrap decline.
For a baseline look at year 2019. 10.376 briths per 1000 and only 283K deaths. That gives a 390K births (on a population of 37.6M). This is already 50K more people added than 2021.
The entire unsustainable trope is nothing but a farce. If Canada's birth rate keeps declining this is the only solution.