I really have never quite understood the enmity that Greenwald inspires, mostly from the "Center" to the "Left." Journalists against journalism are bizarre, as are people who think revelations about the Surveillance State are somehow direct attacks on Obama. Yes, ultimately, the guy in charge is the guy in charge and I haven't seen a lot of evidence he disapproves of much of this stuff, but it isn't really that simple. One can think in combination that the surveillance state is out of hand, some programs might be "worth it" but not all, that Obama doesn't sign off directly on every program, and that even if he doesn't support all of these things it isn't so simple to turn over the bugged applecart instantly.
Even if I trusted Obama completely (I don't), and even if I thought he knew as much about this stuff as he should (I doubt it), I can't imagine trusting the massive unaccountable agency. Even if I trusted the nice patriotic government workers, I wouldn't trust the massive private contractor system that has grown up around it. Snowden showed how easy it was to "abuse" his access. You think he's the only one? (We know he isn't, of course, we just don't know how bad it is).