We've used it and competing workflow management "languages" -- there are a few of them -- in our bioinformatic processing pipelines. "Sophisticated bad joke" is a pretty accurate description.

It's used in bioinformatics. for example by the Global Alliance for Genomics and Health[0].

You can find some CWL workflows on dockstore [1].

[0] https://www.ga4gh.org/ [1] https://dockstore.org/search?descriptorType=CWL&searchMode=f...