Hidden task property "deadline" is uneditable to unhide by default

In the standard Task object, there is one and only one property that is hidden by default, and not un-hideable globally: the deadline. To me, this is a bug. Standard objects' properties are not editable, so every single time I make a task, I have to click to unhide the deadline property. And it's only one property, not a big list to choose from.

Please unhide the "deadline" property! Or make hide/show selectable at least!