COBOL is not a good career choice
It is a myth that there are huge numbers of COBOL programmers. For most areas, COBOL applications are being retired faster than old COBOL programmers are croaking/retiring. The applications that will still be around for years to come are mostly on old mainframes. Think IBM and Unisys. Collecting income tax in the USA, running old pension/insurance schemes until they are finished, cheque processing (yes, some people still use cheques), old mortgage systems - these type of applications are not good candidates for rewriting in new languages. The applications are stable and don't change much. They have long been isolated into a back-office environment. The apprenticeship is long. Vacancies for young people or old-timer programmers are very difficult to find.
Biting the hand that feeds IT
