There are many of these schemes not only in China and Japan, there are many of them everywhere. Nowadays, many come from Singapore, usually related to cryptocurrency.
Quite a few of these schemes are based in Russia. Beautiful words, marketing and the hope that you will get rich this time leads people straight into this trap. And of course, financial illiteracy does its job.
Dropping names of country where scam originated is not really good but anyway this is the life of anonymous. Anyone are free to scrutinize without exposing identity.
Scams really come from all over the world. Mostly scammers come from most corrupt country. Scammers were just like being encourage from those countries seeing unsystematic leaders that are corrupt. They just follow what leaders do and this is why others are very innovative creating their ways on scamming. Old school tricks still effective.
Try to.post here that you will buy bitcoin and many users will going to pm you trying to scam you. Some of them are idiot scammers.
Scam is essentially a scam. It cannot be said unequivocally that most of the fraudsters are in corrupt countries, because in order to pull off such scams, you must have a certain level of intelligence.
Those who have it higher are less likely to be caught in their machinations, but they are usually from more developed countries. Take America, there are also a lot of famous scammers.