Alpha channel should not be weighted when using "masks (no sRGB)" texture compression setting

When attempting to import a texture that has a non-opaque alpha content and compressing using the "masks (no sRGB)" texture compression setting, pixels that are in the alpha channel are being weighted as being less important.

1. Launch editor from binary launcher (4.9.2)
2. Create a new blank template without starter content
3. Import the "original_mask_with_alpha" texture
4. Double click the texture to open in texture editor
5. in the "view" drop down uncheck "alpha"
6. in the details panel under compression change the value next to compression settings to "Masks"

Expected:
The pixel values contained within the RGB and alpha channels should be weighted with the same importancy.

Actual:
The pixel values in the alpha channel are being weighted as much less important than the ones in the RGB channel creating artifacts in this area.