How to reproduce:
1. Open project "CopyTexture_TextureArray_TextureQuality.zip"
2. Open "Scene" Scene (Assets>Scene)
3. Select "Textures" GameObject in the Hierarchy window
4. In the Inspector window double click on the "Red Texture Array" window
5. Look at the Texture color in the top
6. Go to Edit>Project Settings>Quality>Texture Quality
7. Set Texture Quality to Full Res
8. Select "Textures" GameObject in the Hierarchy window
9. In the Inspector window disable and enable "Test Texture (Script)" Component
10. Double click on "Red Texture Array"
11. Look at the Texture color in the top

Expected result: The color in the Inspector is the same color like Texture Red
Actual result: The color in the Inspector is white

Reproducible with: 2020.3.18f1, 2021.1.22f1, 2021.2.0a14
Not reproducible with: 2021.2.0a15, 2021.2.0b12, 2022.1.0a9
Could not test with: 2019.4.30f1 (Texture color is not showing, it's showing the texture logo "texture.png")