This is actually more common than you'd think. There are plenty of older wooden boats still fishing both in the lower 48 and up north. The old halibut schooners are some of the most prized boats out there.
Ha, I just left a job that had multiple VB6 apps and services that we were actively maintaining and extending. Getting the development environment setup wasn't too bad. What drove me bat shit crazy, was the fact that the mouse scroll wheel isn't supported in the IDE.
I was part of the third team that left in as many years. Just another lesson of a single individual being the only decision maker across all departments.
It was kind of sad everyone came in trying their best to improve the software and environment, but they were quickly shot down by their boss. If you didn't copy paste his code you'd get a snarky email a few days later about not following the guidelines, that were never written down mind you.
My lesson for rewriting a legacy application, have the right management in place. If there is an old dev that does not want to change, the project is a waste of time and money, he'll have more sway over the executive team and often get his way.