There’s obviously that big market of people who like Single Player games. But they never made Titanfall for that market. The same way league of Legends or CS:GO or the upcoming Overwatch are not for that market.
I wrote about this quite recently, how people want everything catered to them. Niches and specific markets exist for a reason. Not everything needs to be a PG-13 Marvel/Disney experience.
In any case, Titanfall failed to acquire the market they sought out for. I hope they do a better job this time around.