I am not sure whether my idea might be true, but it could be that they just want to use japanese people to port their games.
While I worked for a publisher (for DVDs though), the arrogance and pride of their products was really high during negotiations. I can think that maybe the same is true for games. They dont want a foreign company to "touch their code", so they want to do it by themselves, but actually japanese devs cant port well.
Thats just a theory of mine.
It is possible.We cant really understand the mindset of eastern companies.They got amazing cultural differences and also their ego and pride might hurt them in the end by excluding Steam and PC.
I mean why cant SE port FFX or FFXV to get extra sales for like minimum cost?(Those games are rumored to come but its not confirmed).I am getting baffled by the executives working for game companies.Isnt the revenue and $$ supposed to be their end goal?