> if they enabled them to be born and survive and become skilled or wealthy enough to be in a position to migrate to western countries on that basis, yes I do think there is an argument that they have some non-zero obligation.
That's a fair point, but I guess the question then becomes - is that non-zero obligation greater than the emigrant's personal quest for a better life. Which, in the real world for most people, seems to be no.
> Let's not lie to ourselves about this being some kind of altruism or net positive outcome
Probably the best outcome for collective human knowledge would be to develop every country, research in every single country = more total research / unit time. But for individuals who just want to be able to invent something in their lifetimes and have a better daily life, this is very far away and humans are bad at long-term decision-making.
> Also do you think the 0.01% of people in a western country have any obligation towards the 99.99% of people in that country?
I don't think so. That's actually similar to the premise behind Ayn Rand's novel Atlas Shrugged [1]. But, I am very happy that we share the same world and I the same country (US) with some of the best people in pretty much every field.
[1] https://en.wikipedia.org/wiki/Atlas_Shrugged