Clubhouse from the beginning was just a bunch of vapid hot air about how cool Clubhouse was, without any substantive backing behind the supposed coolness except for all the VC-backed users constantly saying how cool it was.
When Clubhouse finally opened up to a wider audience of people who weren't being incentivized to use it, new users churned out almost immediately because it wasn't actually very cool at all.
Basically, the story of Clubhouse was the story of Google Glass.
I think that's what happened regardless of how it sounds. Until it was an elitist iPhone only app, it had a cool vibe around it, but I suspected once they open the floodgates most people will realize how little value it has. Then they probably couldn't handle the traffic and new issues. I'm not saying there's any problem with Android users, but building a community on a single mobile platform for a long time then mixing it with another was probably a bad move.