The pattern I've noticed is that if the entire building/floor/cube farm is "you ain't getting in here without clearance" or "nothing in here requires clearance

The pattern I've noticed is that if the entire building/floor/cube farm is "you ain't getting in here without clearance" or "nothing in here requires clearance" then cube farms are acceptable. Most places with cube farms also provide something to string across the opening to prevent accidental NTK violations. You'll have oversized cube farms that are half empty even though the rest of the building is packed like sardines because they've determined that nobody else has a NTK for whatever the team occupying them is working on. At some point it comes down to common sense and cost, level of secrecy and expected lifetime of secrecy (the requirements for a sub propeller are different than something that's being production-ized so it can be issued to thousands of soldiers). The only buildings/floors I've seen that are all offices either were management or super secret algorithms and electronic systems integration projects. Like the kind of stuff where the "old boring legacy tech" exceeds the kind of stuff Hollywood shows you.