Or they could just "Get-CimInstance -ClassName win32_operatingsystem | select lastbootuptime" (100ms).

Or "wmic os get lastbootuptime" (500ms)

Or, hell, net statistics server / net statistics workstation (200ms) if, for some insane reason, the servers are allowed to Sleep.

I'll never understand "admins" who can't figure out that the screwdriver isn't a power-saw...

That's actually the *sole* purpose of the government.

Unless you want a society completely based entirely on the notion of Survival of the Fittest, but I doubt you've got enough weapons stockpiled to handle that kind of world.