UnityEngine.XR.WSA.WorldManager is obsolete.
What is the up to date alternative for
UnityEngine.XR.WSA.WorldManager.GetNativeISpatialCoordinateSystemPtr();
or has WorldManager moved home?
Support for built-in XR is removed in the latest Unity version. The WinRT API, such as Windows.Perception.Spatial.SpatialLocator is the alternative for it. For your case, you can use var spatialCoordinateSystem = SpatialLocator.GetDefault().CreateStationaryFrameOfReferenceAtCurrentLocation().CoordinateSystem;
to create a coordinate system with the origin placed at the device's position as the app is launched.