The Daily Prebuilt API has introduced several updates to improve the user experience of broadcast calls, including configurable options such as private vs public rooms, prejoin UI for hosts and attendees, knocking to enter private rooms, chat functionality, and additional settings like participant tiles and local video. These updates aim to provide a more controlled and anonymous environment for both hosts and attendees, allowing for a better flow of conversation during the call. The API also includes features such as waiting messages for attendees and "host has left the meeting" views to simplify the UI and manage multiple hosts in calls.