Sounds good in theory. But in practice?
Both you and I left our homes countries to find better lives - and neither of our countries were as bad as most of the places these people come from.
In theory, I see your point. In reality, though, most people want what is best for their family and kids. If they see a better future elsewhere (rightly or wrongly) they will pursue it. People willing to pay that kind of money to get to another country are more likely to work hard and be productive in that country to recoup their investment.
Especially if I had daughters, I would be out of most of those countries. Even in Japan, I advise my daughters to look outside Japan for opportunities they won't easily find here.