If it is simply their hosting company that did this, the owner of the domain can just find another host.

If the domain was taken, that's a different topic.  But the domain's last update was a few days ago.  Maybe they recently moved to a new host or something and the new hosting service gave them the boot (by causing the http 451 error).

bitcoin

Nitter[.]it instance down because of "illegal content"

cryptocoin

If it is simply their hosting company that did this, the owner of the domain can just find another host.

If the domain was taken, that's a different topic.  But the domain's last update was a few days ago.  Maybe they recently moved to a new host or something and the new hosting service gave them the boot (by causing the http 451 error).