You certainly identified the many flaws in Hansen's pronouncements. Hansen's unscientific behavior has been a deep embarrassment to many scientists in NASA and in GISS. I agree that Hansen has never been muzzled, but just threw out the allegations because he knew he had willing accomplices in the MSM.
I also agree that Zágoni's claims have substance. That is why it is puzzling that he would be muzzled. I have (or had) a deep respect for the scientific integrity of the NASA team in general, but have been somewhat concerned about the possible political-motivated origination and, more recently, the politically-motived direction of the Earth Science program, especially in light of the lack of discipline in Hansen's case.
NASA's always kept a good eye towards funding, but that's any bureaucracy. Bureacracies can be remarkably Darwinian when it concerns their institutional survival.
However, to your point, I don't know that "NASA" as a whole is suspect. GISS is another story. Spend some time at Climate Audit and you'll be amazed that someone doesn't simply shut down or clean house at GISS.
In all fairnss, I should have noted that Hansen did ultimately release the source code, though grudgingly.