Interesting quotes from the article:
"Even on an extremely high level, I think they have more things in common," Bach told MMGN in an interview last week. "It's much easier to develop and to deliver on five platforms, which is good for us."
both consoles now offer an x86 architecture
It's not like PS4 or Xbox One are particularly hard to develop for. Quite the opposite: you can make whatever you want on either one, and that should be enough for anyone."