and probably because there are more jrpg players bought sony console. traditionally, sony playstation was the home of the greatest jrpgs. and also because they are fellow japanese companies, I guess?
Xenophobia, combined with a cultural dissonance about anything originating outside their home islands.
We've been seeing that for years from Japanese companies... it's appalling, but not surprising anymore, and that's sad.
Japanese dev houses, and Japanese console makers for years have been keeping regional exclusives. Remember Mother 1, and 3? The only
good 16-bit BTTF game? the only good Godzilla game of the same era? The Neo Geo version of
Super Dodge Ball that we can't even buy legitimately?
Japanese dev houses especially treat PC like a third-class citizen. Remember Resident Evil 4? Un-remappable key bindings and an impossible default key map unless you gave up and plugged in a 360 controller. The Dynasty warriors games forcing a 30fps frame lock, even when there was nothing about them that technically required it. Or Final Fantasy XIII ONLY outputting in 720p, regardless of what your system was capable of.
I'll admit I never played disgaea, but I find myself fearing on behalf of its fans, wondering what kind of plague-like awfulness the developers have in store for making as unnecessary limitations on the PC release.