EFF Item attribute with 'Radio Button Group' display type not visible while creating item in PD

Why the EFF Item attribute with Display Type: 'Radio Button Group' doesn't appear in the required attributes while creating and Item in PD even thought the attribute is involved in a valid/active Item Rule to update the Item Description?

My understanding is that the item attribute is supposed to show up while creating the item even though it's not mark as mandatory because it's part of a Item Description assignment rule.

If I change the attribute display type to other different than Radio Button Group, then it appears while creating a new item in PD, there seems to be something wrong with that attribute display type specifically .