You're right it's more than 6. The 190 figure probably comes from the number of "countries" that were restricted from purchasing the game after (and only after) the PSN account linking was announced. Steam defines a lot of territories and unrecognized regions as "countries". Supported PSN countries are listed here https://www.playstation.com/country-selector/index.html

E: Actually some of the countries in the selector aren't supported for PSN either (at least PH), so I'm no longer sure if there is an offical list of supported PSN countries anywhere.