I'm not sure leadership believed anyone was all that valuable. The general impression was (and still is, sadly) that we were all worth more fired as cost savings than we were employed[1]. The only thing keeping them from doing your kind of shenanigan was probably the hit to NIST / FEDRAMP / whatever else that can get you blacklisted as a supplier.
I remember one single exception. One of the regular rotating layoffs took out this one engineer who had extremely niche knowledge when it came to microphones. Like, there's four other people on the planet who do the math this guy does. But he's on the list, so there he goes. Pink slip, boxes, guards, parking lot . . and then they call him back in before he even gets everything packed. Someone must have run upstairs to yell at someone important - I mean, this guy wasn't just "make new things" sort of skill, but also "keep everything else working" sort of skill, peppered with "the FAA will get extremely angry if we don't have this sort of thing" skills. Luckily, he was a canny old gent, and replied on the spot: "Sure. I'll come back in. But it's gonna cost ya." Rumor was he managed to double his wages, and get a stock thing to boot. That still brings a smile to my face, many years later.
[1]The monkey wrench is that Cost Plus pays for hours, so they're gonna try and get those hours cheap as they can. This is one of the reasons they haaaaaaaated hourly headcounts - see, you pressure your salaried people to stay 50-60 hours, but you keep billing the DoD for hours, and it's like free money. Hourly, that doesn't work so well. They converted literally everyone to salaried as soon as they possibly could.
