I recall that the 1.1.1.1 block page doesn't serve the real one,, but the challenge page that they serve normally does. Maybe I'm misremembering? or maybe they changed it.
I just tested and it's the "real" recaptcha, with requests to google and everything. It still might be "fake" in the sense that the server rejects any response, even valid ones, which is probably what's actually happening.
>archive.today doesn't use a real recaptcha
How? It's loading the script from google, and the images/responses are from google to.