This might grow bigger than cobol.
There will be a large number of companies that will be staffed entirely by vibe coders and when an issue crops up that cannot be debugged by them a consultancy will be brought it. The consultants will use their superior agentic skills supported with actual coding and software archeology experience.
Some other companies will have both vibe coders and systems engineers on staff.
I’m just making this up, it probably won’t be like that. But it’s interesting to think about it.