I wonder if we've reached the point where many of the people who would have been using CGI scripts (if they had not been succeeded by newer technologies to provide dynamic functionality) no longer know what it is.
I am pretty sure we reached this point quite a few years ago. From what I know, most people learning web programming nowadays start with Rails, Express JS or whatever framework of the day they have been recommended, and use the integrated HTTP server for development, I would assume, often without even really worrying about what is actually happening. CGI scripts are definitely not on the list of things to learn there.