Is Canada much colder than Australia?

Geographically speaking, Canada's overall latitude is on the high side, which is indeed much colder than Australia. Especially in Toronto, it is very cold most of the year. But in cities like Vancouver and Victoria, the temperature is relatively average all year round, and the average temperature in winter is almost above zero, which is not very cold.

I think it's a bit strange that climate is the reason for choosing an immigrant country. Shouldn't it be based on its own development?