I am a retired DOI employee (but not NPS) and can relate to what is being reflected. There's also a lot that isn't being said. There's no mention of politics for instance and that's a really frustrating factor in the DOI and the Forest Service (DOA). The agencies are often caught in the middle of political battles between those who want revenue from public lands and those who don't want to touch anything anywhere. Lawsuits abound and affect what can be accomplished. A lot of staff time is spent just dealing with legal squabbles. Also, every election there's a change of staff at the top,priorities are re-arranged, and budgets re-directed. That's because with the exception of the chief of the Forest Service the top jobs are political appointees and not Civil Service employees. So, get a different president and you get a new Secretary of the Interior, a new boss for your region, and a new set of priorities.
The "diversity" thing is also problematic in ways not noted in the article. I don't want to get into an argument here but will just say the statistics about if employees feel candidates are selected or promoted due to merit are revealing. Also, unlike the private sector, money is not a promotion or reward factor. One gets promoted - at least beyond the very early grades - based largely on how one plays the political game. The reward is more power and not big money.
As has often been said one can't live on beautiful scenery. Permanent jobs and promotions are hard to get and one does have to move and live in places that don't offer much except the job. One way agencies deal with budgetary shortfalls is just to not hire permanent employees (similar to the private sector but accomplished in different ways). So there's lots of "permanent" seasonal employees.
There are, of course, lots of positive aspects but they don't involve money or perks like a company car or even a special parking place. Generally, people working for natural resource agencies are doing it because in the end they love being outdoors and dealing with the natural world and they're willing to trade a lot for the opportunity. Natural resource jobs are also generally blue jean jobs and you get out of the office.
Oh, and there's also the opinions of the public about federal employees. When the stock market is rocking people think a government job is one of last resort; can't make big bucks - why would anybody do that if they had any real talent. When times are bad, though, low and behold all government workers are over-paid and underworked and there's way too many of them. But then nobody wants to wait for anything or be inconvenienced either; they just don't want to pay for it.
Ah, yes ... a DOI career means a picnic in the woods every day.