I was working on a project where I wanted to have scripts place upside down shulker boxes but wasn't able to, due to the facing direction being stored in the blocks NBT data which can't be accessed by the /setblock command or scripts.

It would be great if the facing direction were moved to a block state to spawn shulker boxes in different directions other than the default direction.

For now as a workaround, I'm using /structure to place it, but this shouldn't be necessary.

How to reproduce:
1. Open a world in creative mode with cheats enabled.
2. Type the following: "/setblock ~ ~ ~ <color>_shulker_box[" (Replace <color> with one of the 17 color options of shulker boxes)
3. See that auto-complete doesn't suggest any states for the block.
3.1 Even if you run "/setblock ~ ~ ~ <color>_shulker_box["facing_direction"=1]" (Copying how the barrel does it) it will throw an error.