I’ll take a long-term perspective on this. VR and AR are hardware technologies that will eventually reach billions of users. For Oculus to lead the way, they would necessarily either need to grow into a big company or become part of one. Now it will be the later.
Android was also incubated by a small company prior to becoming ubiquitous following a Google acquisition:
are visionaries, and Brendan Iribe has a great business sense. They certainly put a lot of brainpower into making a decision they felt was best for the future of VR.