That's not possible without permissions these days, same as iOS. In Android 13, background processes have no mic or camera access whatsoever.
It was an iPhone, and there is no indication from the phone when the mic is recording.
Android has a notification now when the mic is recording and has had the ability to deny microphone and lots of other access for a long time now. Thankfully it sounds like iOS is catching up
> My wife and MIL sitting at the table talking about a unique topic with an iPhone running Facebook sitting in front of them