True. But i don't think will happen. As we know, games like AC, FIFA, and COD, are continued to increase years after years.
AC peaked in 2012, FIFA peaked in 2012, and COD in 2011. ( at least launch, dunno about LT sales).
I don't think will happen again. Titanfall 2 will probabily sell more than Titanfall, but only because the PS4 version. The game is death in the others platform, and i don't think will be bigger on XBOX. Maybe, just maybe, a bit bigger, but only because XB1 will be at >20 million userbase compared to the < 5 million of March 2014, and who will buy Titanfall already has a XB1.
Destiny, and Watch Dogs... eh, i don't know. The lauch of those games was pretty strong.
Destiny sold 6.3 million worldwide in September 2014, nearly 3 million only in the US, and Watch Dogs around 4 million first week.
After many bad reviews, and the huge hype of the launch... i think those games have already peaked.