I assume the reason is, that it was not considered to be important to see that attribute in other than the plan views. It was designed for the planning purpose and only for that - that is why it is administered in that section.

If you want to see the the new attribute (blocked) in other editor presentations, you can add it there showing the boolean value. I have not been involved n the design, but I can't see a special presentation for the comment, so I am unsure if that can be shown (and if it is even something that is stored with the work item). It can, for all I know, be stored in the plan and not in the work item.

If you want more features around this, please consider to create an enhancement request.