Texture becomes lower quality when the texture is downloaded with script

Reproduction steps:
1. Open the attached "(FAV) PROJECTFILE" project
2. Open the "Assets/Scenes/SampleScene 1.unity" scene
3. Enter the Play mode
4. Observe the Game view

Expected result: The “Original” and “Downloaded” textures have the same quality and have no differences
Actual result: The “Downloaded” texture quality is lower compared to the “Original” image

Reproducible with: 2021.3.29f1, 2021.3.33f1, 2022.3.14f1, 2023.2.3f1, 2023.3.0a17
Not reproducible with: 2021.3.28f1

Reproducible on: macOS Sonoma 14.1.1 (M1 Max), Windows 11
Not reproducible on: No other environment tested