I don't code in Cobol myself anymore but I manage team who does.
We work on Phoenix, government of Canada payroll system. If you google it up, you'll see some interesting coverage. However, the underlying peoplesoft ERP itself is rock solid at every other client I've served over last 25 years. Peoplesoft uses Cobol and sqr, as well as proprietary languages stored in database, application engine and peoplecode.
Key payroll processes are in Cobol. This is because of its tight integration with database and ability to manually control database cursors. We are very database oriented when it comes to performance. Our developers need to know the programming language, but also deep understanding of client business processes, and sql optimization. They also work closely with our dbas to ensure good performance. So our developers are technically proficient in Cobol and couple of other languages, but also very very strong in sql optimization, and understand clients payroll rules and can speak intelligently with compensation advisers and payroll processors.
I personally found that to be true for most Cobol programmers - whereas typical hacker news Dev seems very technology oriented and frequently moving, typical Cobol programmer is very business process aware and integrated with corporate line of business. They don't move as much for several reasons, but that deep awareness of client is one of them.
Edit: I shoild mention, while peoplesoft can and does work on mainframe, most of my clients are on windows, Linux, or AIX. COBOL is not quite as mainframe specific as it sometimes seems :-). See e.g.microfocus Cobol for a modern multi platform compiler.