Honestly, any other year, this would almost certainly have been published on the 1st of this month as a joke, but it appears to be legit. Cloudflare Workers (which are a very easy to use FaaS offering) support the use of COBOL to write your functions. Is there any real practical use for this? Not really. I guess it could be a way for you to practice your COBOL if you are learning it to help out with one of the many legacy systems which are being stressed by Covid-19. Enjoy.