This smells like something happened with MarkMonitor, they accidently flagged zoom.us as brand spoofing and filed copyright complaint with GoDaddy who runs .us TLD. GoDaddy suspended the domain per the complaint.
replies(3):
ServerHold is used with Registry (GoDaddy in this case) is disabling vs ClientHold is when registrar is pulling the plug (MarkMonitor)
So what would have MarkMonitor said to GoDaddy to cause them to ServerHold a domain?