How to reproduce:
1. Open the “ReflectionProbe.zip“ project
2. Open the “TerrainDemoScene“ Scene
3. Find and focus on the “Plane (1)/Cube (1)“ GameObject
4. Observe the Scene view

Expected result: Reflections look similar to “Plane/Cube“ GameObject and have no artifacting
Actual result: Heavy artifacting and no reflections near the cube

Reproducible in: 2023.1.0a1, 6000.0.57f1, 6000.2.3f1, 6000.3.0b1

Reproduced on: Windows 11 Pro (24H2)
Not reproduced on: No other environment tested

Workaround: Generate the lighting

Note: The behavior is a bit different in 2023.1.0a1 (there is no artifacting), but it looks similar to 6000.0.0f1, so I believe this is an indication of this still being reproducible