Yeah but these things are built from scratch. Your average ages-old Borland or whatever suite with its build script? That's a lot of work to integrate with a modern IDE, and honestly I wouldn't risk it in that space either due to the potential for things to go horribly sideways. So you need at least the OS and build tooling combination that was used for the last certified build, and if certification requirements are really strict you can't do that in a VM but have to develop on age-appropriate hardware as well.