When sRGB (Color Texture) is true vs false there is a clear visual difference in Linear space.
In Gamma space, however, it has no effect.

Steps to reproduce:
1. Open user's attached project
2. Open scene "TestScene"
3. Open folder Assets/Maps. Notice: "sRGBChecked.png" has sRGB checked. "sRGBUnchecked.png" has sRGB unchecked.
4. Player Settings > Other Settings > Color Space: change between Gamma and Linear and enter Play mode

Expected behavior: The middle sphere (the one with sRGB checked) looks same as the right one on both Linear and Gamma.
Actual behavior: The middle sphere is same as the left sphere in Gamma.

Reproduced with: 2017.2.0a1, 2017.1.0b7, 5.6.1p1, 5.5.3p3.