I think the larger issue here - and Allyn points to it pretty clearly - is that Abrams came to understand through this frustrating process that shortsighted corporate turf wars were going to prevent growing Star Trek to its potential. Why should someone who has so many opportunities bust his ass for a retrograde corporation that doesn't get it when he's being offered a far more attractive situation, one which is apparently open to all the ideas he had for Trek, with Disney and Star Wars?