[Bug] Raycasts flicker against ARMesh on Quest 3

[camnewnham]

Unity bug report case number
IN-77947

Describe the bug
Video describes it best. Raycasts do not consistently hit the mesh provided by the ARMeshManager (Meta OpenXR, Quest 3).
While this repro uses interactors to demonstrate this, it also occurs just using plain old Physics.Raycast.

QUEST-ISSUE-RECORDING.mp4

To Reproduce

1. Create a new project in Unity 6000.6.4f1 and import the XRI Starter Assets sample. Add dependencies (Quest OpenXR, ARFoundation , etc.)
2. Add an ARMeshManager and an ARMesh prefab containing a MeshRenderer, MeshCollider and XRSimpleInteractable
3. Add a XRInteractorReticle to the controllers help visualize the issue.
4. Perform Space Setup on Quest 3 to get a room mesh.
5. Build and run the project
6. Go to settings/privacy and enable spatial data sharing
7. Return to app
8. Observe environment is visible
9. Observe interactor flickers when moved over the spatial mesh

Expected behavior
Raycasts consistently hit the spatial mesh.

Actual behavior
It appears as if every second raycast misses.

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This isn't directly related to these samples as it's using the XRI sample project, but since it's using the ARMeshManager I figured this was an appropriate place to report. Let me know if it belongs somewhere else.

Related (?): it appears that ARMeshManager updates more or less every frame on quest with a very slightly modified transform for the mesh.