Nobody can predict the future, not even you. So you have no idea if that would have an effect on the economic output of those countries (which is what you mean

Nobody can predict the future, not even you. So you have no idea if that would have an effect on the economic output of those countries (which is what you mean by "wealth" even if you don't know it). One thing we do have an idea about and can say with certainty about some of the effects it will have on the people in those countries. We can say with certainty that 400, or 4000, or 40000 people will become less wealthy, and everyone else will become less poor.