Would you settle for any old static page served by Cloudflare? For instance, example.com? https://bgp.tools/dns/example.com
Maybe Cloudflare gives them a good rate, or is donating service, but it's also possible or even likely that IANA is just using Cloudflare as a vendor, and therefore is paying for all the traffic, which is why they don't want people relying on it or hammering it all the time
In the nomenclature of RFC 2119, one MUST NOT design computer systems that rely on the correct operation of an HTTP server at [example.com.] Plus, it's *_really_* rude to pound on a small-scale service being provided as a courtesy.Much too big for metered data, full of ads, and importantly they all mandate HTTPS these days, which breaks my use case of forcing a captive portal on paid/login-gated Wi-Fi to render.
example.com is (unfortunately for the IATA) the almost perfect "can I reach the Internet" service: It's unlikely to go away, supports HTTP, is fairly small, easy to remember, and I don't care if a captive portal poisons my DNS cache with a fake response temporarily.