There were 2 company named Clubhouse before.
One was a Social Video App company ( Hereinafter as “Clubhouse App”) which use the domain JoinClubhouse.com
Another was a Software Company focused in Collaboration Products (Hereinafter as “Clubhouse Software”), which use the domain Clubhouse.io.
It is interesting that none of them use the perfect domain Clubhouse.com.
What happened later is more interesting.