Interesting you mention CGI; I built https://bigcgi.com (https://github.com/bmsauer/bigcgi) primarily to address the issue of "any language" in FaaS environments.

Seeing this takes away one of my biggest comparative advantages, but I'm happy to see that at least I was not wrong in thinking this feature would be important for developers.

CGI still has the advantage of being an open standard, locally testable, and not vendor specific.