It seems to me that Stephenson just likes East Asia a lot, I wouldn't be surprised if it turns out he lived there. E.g. Cryptonomicon has detailed geography and

It seems to me that Stephenson just likes East Asia a lot, I wouldn't be surprised if it turns out he lived there. E.g. Cryptonomicon has detailed geography and economics of the region in play, many of the other novels have events set in there―and in the pretty recent “Reamde” he again spends plenty of story time in Xiamen and some in Manila, even though the book is set in the present and there's little cyberpunkish about it. I'm actually sort of learning from these books about the vibe of the region, some scraps of relevant history, and the area's economic relations with the US. Because otherwise it's mostly fantasy land to me.