It's also possible that those inside the system have more information about what is going on and why. HN is often working on a very worst case assumption when it comes to these stories whereas internal employees probably have a lot more context about what is actually happening.

They'll also probably being seeing the internal disfunction of their organisation, as every insider does. From the outside the NSA, GCHQ etc seem scary, omniscient, omnipresent and omnipotent beings. If instead you know the people doing the work, the internal politics etc you might be less afraid that the rights of normal people are being infringed.