No game has ever had a major hardware related component added post-launch. Splitscreen on last-gen would make the game literally unplayable. Splitscreen on next-gen would offend the delicate sensibilities of people who are already complaining that there is not enough of a graphical upgrade from last-gen to next. Basically, never gonna happen. There are hardware constraints and the fact that many people buy two copies of video games to solve this problem for themselves. Publishers do not like splitscreen. Splitscreen is dead. I guarantee you that this now current gen will see an end to splitscreen games in all but the rarest occasion and indie titles.