MS seriously needs to hire new PR people. Their messaging is consistently a disaster.
If this is a timed exclusive, I don't see what the big deal is. Is any PS4 owner really going to choose RoTR over UC4? I'm sure there are a few, but they will be the exception. By 2016, after UC4 is bought and played, players will be ready for another pulp adventure and RoTR will have a chance to get decent sales. Otherwise it comes out head to head with a very similar game that has more hype and gets forgotten in the holiday rush. MS gets to avoid inevitable X1/PS4 comparisons, which it will lose, and gives its customers an alternative to UC4 which they will never get without buying a PS4. It's a rationale business decision that minimally effects PS4 owners.
If this is permanent... I really don't know what MS and SE are thinking. RoTR won't move a lot of X1s for MS, and SE will be sacrificing a larger audience, all while screwing over customers and fans of the series.
I can't imagine either MS or SE is dumb enough to make this permanent, and I believe CBOAT. So ultimately this is a lot of fuss over something that will hardly affect anyone beyond the most diehard TR fans that only own a PS3 or PS4.