Would not be cheaper to fix those unsafe languages, such as C, and offer safe mechanisms that could be used upon need? Why spend thousands, if not millions of dollars, on rewriting existing codebases when they could help fixing the existing toolset and make it safer? I don't get it.
In the same idea of "Any sufficiently complicated C program contains an ad hoc, bug-ridden, slow implementation of half of Common Lisp." let's paraphrase
Any sufficiently safe C program contains an ad-hoc (etc.) implementation of the infrastructure needed to make it safe:
- custom string implementation
- custom object/memory management
- custom memory slices and other data structures
Not forgetting the compiler tricks added to try and catch when the program does something stupid