I mistakenly called them lazy in a previous post. I think's it's a choice as to what to spend developer hours on and they have chosen other things as a priority. It's probably coming from the top.
If I buy 24 hoping they will bring back y2y in 25 then I'm Charlie Brown convincing myself that Lucy won't pull the ball away. If the see a significant decline in people playing 24 franchise mode then they might decide to spend developer hours on y2y.