truematter I think the global legal situation also plays a big role. If there is no industry, there will be no performers. If you look more closely at scenes that are tagged Indian or Chinese or Korean or African, you will find that these are all from performers who were maybe born there but at some point in their life moved to the US or Europe.
And about those VR videos filmed in Thailand: On his website, the guy claims that he moved to Asia since he was 'seriously fed up with western female attitudes' and claims that Asian 'Girls actually LIKE men and want to please them over here'. But in his videos, many girls (who may be working girls and not performers) look as if they'd rather be somewhere else and don't seem to enjoy it. This is sometimes disturbing to watch. Therefore, before supporting shady businesses exploiting women, I rather do without the diversity and stick to the performers that are available in those countries that have an established and legally operating industry.