Here’s the thing about the immigrant pulled-up-by-bootstraps story: immigration is expensive. When you hear about someone coming to North America with “only a few thousand dollars in their pocket”, you have to remember that by time they’ve landed, they’ve already sunk likely tens of thousands of dollars into getting the paperwork to get here (unless they already had a job lined up, which generally means educated).
Many not-poor people I know in Canada wouldn’t have the means to immigrate elsewhere without saving up for a few years at way above minimum wage. Education and skill are going to make them more desirable immigration candidates than, say, someone who barely graduated high school. It’s really not an apples-to-apples comparison at all.