Please, you can say "be careful, be cautious, be polite", but not "if you are Western the it's totally forbidden for you to write fiction set in a no-Westen civilitation". We shouldn't close that door if this could be a good hook to try help to know better those cultures. The own Asians are the first who would like to use the speculative fiction as a hook to introduce their own titles into the western market, to build a bridge between the different cultures. In the right hands the heroes from the speculative fiction could be good "ambassadors" in other countries.
If I create a homebred setting based in a mash-up of my favorite mangas, I add fantasy races, and real world is replaced with a fictional planet, who is going to complain about annoying stereotypes and why, why now and not when the original manga were published? If my stereotypes showed in my stories are annoying, then also should be when the originals where I get the ideas were published.
* What new PCs races based in Asian folklore would add to D&D?