How persistent is the storage of the WorldTrackingProvider and its underlying world map reconstruction?
The documentation mentions town-to-town anchor recovery, and recovery between sessions, but is that including device restarts and app quits? There are no clues about how persistent it all is.
World anchors are persisted across device restarts. We have a new developer sample, Object Placement which demonstrates this. You can download it on
https://developer.apple.com/documentation/visionos/tracking-points-in-world-space
Take a look at file PersistenceManager.swift in particular.