@freemo They've marked the domain as malicious, so anyone using Quad9 as their DNS resolver, won't be able to reach mstdn.social or qoto.org as they dont resolve:
QOTO: Question Others to Teach Ourselves. A STEM-oriented instance.
An inclusive free speech instance.
All cultures and opinions welcome.
Explicit hate speech and harassment strictly forbidden.
We federate with all servers: we don't block any servers.