Is CLIST’S still used today? or is it in a phase out stage?
COBOL is a programming language and the code is usually run either via a transaction (within CICS), or in batch via JCL. To build JCL, control your working environment and for other needs, CLISTs are often used as a scripting language. REXX is used too, but less frequently.
Like SAD commented, yes it’s still a viable part of the landscape. However you can (and should) run other ho$ted language$ on z/O$ these days. Just get your checkbook out , it ain’t cheap.