Though I'm not gonna lie, to me it felt like it was all building up to
Final mission spoilers ahead
Michael, Lester and Franklin deciding whether or not to kill off Trevor who was pretty much the main antagonist of the game when you think about it, just not in an obvious way like some of the classic villians. They kept hinting at throughtout the game, with Michael calling him "uncontrollable", the FIB guys being cautious of him and addressing that he's a problem, the whole Trevor turning and wanting to kill Michael after finding out about Brad and then him threatening Franklin. He also does the worse things in the game and is made to be the most hateable character to people. That's what I thought the end game was heading to, I was shocked to see Michael's as a name that you could kill. It should have just been Kill Trevor or spare Trevor, the whole stuff with the Chinese, Devin and the FIB guy should have been before that decision.