Is texture storing color data?
This setting is only relevant when Linear color space is used, and controls whether sRGB->Linear
color space conversion is done when sampling the texture in shaders.
Most "regular textures" store color data in sRGB color space, and for them this flag should be set to true.
Non-color textures are typically stored as linear values, and the GPU should not do any color space conversions. This flag is set to false in this case. Unity marks various non-color textures (e.g. normal maps) as "linear" by default. Legacy IMGUI textures should be set as linear too.
This flag corresponds to "sRGB (Color Texture)" option in class-TextureImporter.
See Also: Linear and Gamma rendering, PlayerSettings.colorSpace.