We call it the Cartmanland[1] approach. Although I think CH is a really nice idea, that too much exclusive thing kept me away from getting an account there even if I have an invite to the platform.

[1]https://en.wikipedia.org/wiki/Cartmanland

What's even more annoying is that Clubhouse requires access to the entire contacts list/address book if you as a user would like to invite someone else. You can't invite someone by just entering their phone number (since a phone number is the only way to register for it). It doesn't have to be this way, but the Clubhouse team doesn't seem to care.