How do I delete VIP Mailboxes that I accidentally created? I have no need for them nor do I have any VIP Mail.

Show emails from VIP senders in Mail on Mac

Remove someone’s VIP status

1. In the Mail app  on your Mac, select a message from the VIP. 
2. Move the pointer next to their name in the message header, then click their star . 
3. The person’s VIP mailbox is removed from the Mail sidebar and the Favorites bar; their messages remain in the Inbox.

To remove the actual mailbox, control click the mailbox > Remove from Favourites.

Hmm, doesn't work for Monterey - picas post does. Thanks