Honestly, there's companies that have lost the source code for some of their applications. Or, they depend on components from vendors that have long ceased to exist. I remember there being a lot of consternation around being able to compile and link against binary components that have just been around forever that could never be recompiled themselves. More people "Learning COBOL" was never going to be a solution to that ball and chain. And yeah, LLMs are good in the reverse engineering space too so maybe we'll finally see movement on that in the next decade.