Obviously this guy was fooled by a friend who was using his iPhone to remotely operate the watch (which explains the „we are in control“ phrase). Now in this forum numerous people that simply have a broken digitizer chime in. Case closed.
It wasn't obvious at all to me that that's even possible. But as it turns out: it's an accessibility feature (1) to mirror the watch screen on iPhone in order to voice control it or use assistive touch.
