You saying this as if Sony is 2000 Dreamcast era status right now. EA and those other publishers NEED Sony. You can't look at Nintendo's situation and extrapolate from there that the same applies to Sony. Nintendo Wii U wasn't selling good at all for the first few months and coupled with it looking like last gen tech you think they're(pubs) going to waste time making games for it??so if EA tells Sony "Ok since you won't let us sell our products with any type of security we're going Microsoft exclusive" then what? what if Ubisoft, and Activision said the same thing?
when the PS4 that has sold 0 units and the Xbox One that has also sold 0 units hit and you can only get Battlefield, Madden, Assassin's Creed, and Call of Duty on the Xbox One then what? see what i'm saying? Sony has the power to say no but if they do they'll face that wrath. now if they had balls they could say no and let this go to market and have gamers rally around them and shun the Xbox One but you'd have to ask yourself if you were Sony would you gamble on that?
The reason I see a lot of 3rd parties falling back on the Wii U is this: The Wii U looks like current gen visually so far, it's not selling so it's not a real loss to publishers since there is not a huge userbase and then 3rd party titles generally aren't bought on Nintendo consoles.
The potential userbase for the Xbone looks like it will be way less than the 360 so I doubt these pubs are confident enough to lose out damn near half or more of their profits because they wanted to lock down their games.