A lot of people want to work on more cutting edge problems - at present we don't have companies solving healthcare problems with datascience, or self driving cars, or tesla like companies.

There is also a charm of moving to a more developed economy too.

For many people living in developed countries, moving to a developed economy seems like a good way to travel the world. Though it might be more of a mindset and exposure issue, travelling the world is much easier when one earns in dollars.