@sun No, this is a thing, sadly. Many moons ago I tried to get Notepad++ approved for NIPR, but since the gov wants someone they can sue if something breaks, it never went anywhere.
@sun For networked services, all that goes through contractors. They lease rack space in a datacenter or host in govCloud and get paid based on meeting SLAs. Almost always easier going that route than creating a program that runs on the end user's machine. DoD had a massive cloud boner back when I was in.