COBOL is very easy to learn and write if you use it for what it was intended for. If you try to make a crud app or read from a web service, you are going to have a bad time. Trust me, I know. It can be done, but it is not pretty and was kind of shoe-horned in.
We have been trying to get rid of all of our COBOL and get off of the mainframe (many apps have been) for the past 20+ years. We are getting closer but priorities keep changing which keeps delaying that goal.
I love doing backend and db work so I would gladly switch to Go for my new projects. But, I would still need to use DB2, which (surprise surprise) is on the mainframe.