I messed around with it, thinking it seemed interesting and could be useful to know Just-In-Case. One thing I didn't get, until I started messing with it, is that COBOL isn't a general purpose language. There's a whole category of things it just can't do, and if you ask about it you'll just be told "COBOL isn't C". There's another set of things it's really effective at, primarily transactions and large iterations.

Mess around with it if you want, sure. Just realize it's a limited language with specific use cases and you're unlikely to ever touch it outside of those, even as a hobby/"for fun".