Maybe white collar gov't workers are less skilled than their private sector counterparts? Alternatively, they could be "true believers"?

There has to be some way to explain a pay discrepancy if it exists. How does one justify receiving a lower salary for the same amount of skill and work?

That could be. But I also think there are certain projects/work that you can only do in the govt. There are probably very few roles for doing fundamental astronomy science research outside of academia or government, for example. A physicist may turn down a higher paying gig in the financial sector because they want to spend their time studying fundamental physics. Others are probably conservative in nature and highly value the job security. Others, like you mention, may just not be able to cut it in the private sector.

I suspect (admittedly without evidence) that someone in the NSA or Marines are not primarily driven by a paycheck. Maybe that's what you mean by "true believers"?

You might need to define what you mean by "outrageously generous". I've worked in multiple public and private roles and, in general, the private ones were the ones with much more generous packages, in terms of pay and benefits.

I don't know if it's the case in the USA but in Canada it's generally considered within IT that you are underpaid but in return have decent benefits, a pension, and a lot more job security than private sector. Especially as Canada has had multiple large IT companies that collapsed.

>Maybe white collar gov't workers are less skilled than their private sector counterparts? Alternatively, they could be "true believers"?

This worldview would also mean that blue-collar employees in the government are more skilled than their private sector counterparts, no?