No migration of this magnitude is blocked because of engineers not "bothering" to start the process. Imagine how many approvals you'd need, plus getting budget from who-knows how many government departments. Someone is paying for your time as an engineer and they decide what you work on. I'm glad we live in a world where engineers can't just decide to rewrite a life or death system because it's written in an old(er) programming language. (Not that there is any evidence that this specific system is written in anything older than C++ or maybe Ada.)