Yeah... I don't fully agree with this.
I mean, it's true that Sony presence in Japan has been waning and becoming smaller every gen(even if the 8th gen is going to do about the same as the 7th gen), but the reason why Sony is not doing as well there as it used to do is simply because it hasn't adapted its hardware well enough to Japan evolving tastes.
I mean, just look at the Switch. It will surely pass 20 million units sold there, and has a real shot at reaching 30 million. And is a gaming console as any that have been ever produced, either by Sony or by Nintendo. Just because mobile is doing better, dosen't mean the classic gaming experience can't grown on it's own terms.
My (locked) thread about how difficulty should be a decision for the developers, not the gamers.