We've been discussing this as well, the Virtual Production production value is incredible, are they also standing on a stage outside, and this is all being composited live, with foreground passes, etc. without green screen?
You're right. I thought this was a live event, but the people watching it live are just watching a video, just saw a live photo from twitter. Makes a lot more sense!
Apple spends at minimum a month prior to an event rehearsing. During a live presentation they have people following along with alternate presentations that can be switched to immediately. These are full AV productions that would make producers of Super Bowl halftime shows jealous.