I understand the reluctance but it feels to me like arguing “we should just stick with COBOL because it works.”
For those depending on COBOL code that does the job and has been doing it just well for a few decades, there are approximately zero good reasons to not stick with it.
Eventually all the people who know and are good at cobol will die.
A while before that happens, the people who know it will continually demand more money for their rare skills.
Eventually, the cobol systems out there will need to interface new systems in some way it wasn’t designed to and it’ll be more expensive to shoehorn the remote system than to let the ancient beast retire.
For those depending on COBOL code that does the job and has been doing it just well for a few decades, there are approximately zero good reasons to not stick with it.