Ahem. This is from a month and a half ago, and since he's the one who brought the Netflix idea up in the TrekCore interview in the first place, I would believe him.
Braga may have brought the idea up in the interview, but who is to say that Braga and company would even be involved in a 5th season? Just because people have moved on to other things doesn't mean that a 5th season couldn't happen.
Look at Arrested Development
as a prime example. The entire cast returned for season 4, and almost all of the actors had other projects in development, yet still were able to be part of the series. Not everyone who worked "behind the scenes" during seasons 1-3 returned for season 4, as many had moved on to other projects. If anything, Enterprise
should have some new blood working behind the scenes to keep it fresh.
Schedule wise, there is certainly more freedom to produce a series for Netflix, then there would be for network televison. As long as the Enterprise actors are willing to be a part of it, it doesn't really matter who helms the season. If some people have moved on to other projects, you simply find new people to replace them.