Import Settings - Alpha transparency enables itself.

When sprites are imported the "Alpha is Transparencey" is disabled. If the user selects "Editor" or "Sprite" under Texture Type, then "Default". "Alpha is Transparencey" is now enabled.

Expected:
The "Alpha is Transparencey" should not be enabled on default texture type.

2. How we can reproduce it using the example you attached
- Select 2D Artwork > PNG > Bomb Sprite - Copy (2)
- In the inspector "Alpha Is Transpareny" is disabled.
- In the Texture Type select Editor and then select Default
Notice issue >> Aplha is Transparency is now enabled. The Revert and Apply buttons are now enabled.

Broken: 2018.3.3f1, 2018.1.9f2
Working: 2017.4.17f1, 2019.1.0a14