[ianb]

To add/agree: I think the biggest difference is that CGI dealt in data, and did not have objects/APIs/etc. In many ways it would have been reasonable to skip even that, and pass an HTTP request in on stdin, and get an HTTP response on stdout, with just some minimal sanitizing promises; but I don't think I've ever seen that approach. Coincidence of history I suppose. Anyway, WSGI also carefully avoided any objects, only using standard data structures (dicts/hashes, strings, ints, ordered-associative-arrays, and iterable response). The result is a functional API without an opinions.