alt Hacker Newsthey do use it in their speedtest server.
curl -v https://speedtest.ams.t-mobile.nl.prod.hosts.ooklaserver.net:8080
...
* Connected to speedtest.ams.t-mobile.nl.prod.hosts.ooklaserver.net (2a02:4240::e) port 8080they do use it in their speedtest server.
curl -v https://speedtest.ams.t-mobile.nl.prod.hosts.ooklaserver.net:8080
...
* Connected to speedtest.ams.t-mobile.nl.prod.hosts.ooklaserver.net (2a02:4240::e) port 8080
Probably a requirement from Ookla, so again "They refuse to implement anything that isn't strictly required".