There is one fatal flaw in your logic. The companies that are abandoning the platform are doing so, because they weren't supported by the player base, and they aren't likely to recognize the success of another as success they can have for themselves. They are just going to reach the rational conclusion that the player base fundamentally dislikes them. It doesn't matter how well someone else is doing if they think that there is no chance whatsoever with that audience.
The time for encouraging or molding Electronic Arts is in the past now. It was a missed opportunity that is lost for the time being. The players had a chance to reward Electronic Arts for efforts they approved of last generation, and they chose not to reward them for anything. So now the choice is either you are going to support their tentative overtures, or you aren't going to do that, and they will see themselves out. The time for being picky and choosey is over.
Sometimes in life it gets to a point where you have to make a choice. That is this time at least for Electronic Arts. The player base has only a small window of opportunity to keep them on board, and like I eluded to in my previous post. It is probably more along the lines that the fans of the brand genuinely need Electronic Arts on their platform. If they want their platform to be successful so that they can have more and better games.
I think there is a lot of Hubris on display in this thread. One of the reasons that the Game Cube though it sold poorly was just able to survive on the market is that Electronic Arts supported the platform. You remove them from the equation, and what you have left is a console with actually more minuses then the Game Cube had, and that is a very dangerous situation for the console to be in at any point in its life cycle. Being early on is a very bad sign. Nintendo doesn't have the casuals locked in. They have probably shed a good number of brand loyalists due to their aggressive focus on the casual market, and their competition is probably going to come back at them very strong.
That all said I didn't even touch on what is actually truly scary. If Electronic Arts abandons the platform. That could encourage a number of other third parties to do the same. It could seriously undermine developer faith in the platform as being viable, and that could result in a rush away from the platform. Anyway I think the platform is in a hole with developers as is, and supporting the developers that are staying doesn't resolve the issue of being in the hole.