Notice how in both scenarios you highlighted headcount increased during the recession itself, and then dropped afterward? That’s because they’re divorced from reality with (as you point out) ever-increasing budgets.
Not saying we should be mean to government workers. But I’m not exactly shedding huge tears for them. They get a lot of perks private employees don’t and the risk they take on (albeit very, very small) is income interruption from politics. Also after the 2013 shutdown the furloughed employees received back pay.