I believe that calling this "discrimination" is a bit too... unrealistic.
There are legal, economical, political, social and cultural circumstances that doesn't provide to a proper exchange or agreement. As well there are cases that companies don't have the licenses to promote themselves in specific countries nor can export money to them due to International Affairs and relationships between the two countries involved and sometimes is not an issue from the company's country, but the one excluded. And, agreements to change a situation to allow the entry of USD to said countries by a specific company, can take years, especially if there are laws about declaring your USD, having to convert them to your currency, taxes, laundering issues and so many more things.
As well, we must have to understand that even if we try to blame USA for everything... Tapas and Webtoon while they have employees located in LA and similar places... these are not North American companies, Webtoon and Tapas are originally from Korea. So imagine... you have the korean companies controlling everything, with their laws, with their guidelines and stuff, then they need treasurers and representatives in their sub-companies, underlings, etc. who are also filtered down by the laws from their respective countries and to that you have to add that there are the other countries where creators come from and they also have their own regulations and laws.