I would say K-Pop Demon Hunters was made by Sony in Asia, just because they did not believe in it and sold it to Netflix is not a reason to not add it here.
But you are right, Vietnam and other asian countries are completely ignored.
It was made by Sony Pictures Animation in LA California, animated by Sony Pictures Imageworks in Vancouver and Montreal. People from Korea contributed and were essential to it's authenticity and success but it is still an American made film.
Starting The Last Wife on Netflix and was sad to see it wasn't here. I thought maybe it's because the English name, but nope. Searched the actors and everything. I get they can't add dramas for every single Asian country, but it would be nice to at least have the ones that are on international platforms like Netflix and Prime.