I’m interested in knowing why the exit node the author used had a Cloudflare IP address, despite Cloudflare not running any relays on that IP space as @deadorbit pointed out above.
My suspicion is that this is a misconfiguration on speedtest.net’s end, because I get the same result as the author while visiting speedtest.net via an exit node hosted by Hetzner, not Cloudflare:
Speedtest.net uses Cloudflare themselves, so the most likely scenario is that their webservers aren’t configured to handle incoming IPv6 traffic from Cloudflare correctly and erroneously report the address of their CDN as your IP, rather than your actual IP.
Perhaps the author should use a better tool to determine the real IP of their exit node, or look at the IP shown by Tor Browser itself as highlighted above lol