For me it is the concept of registering to vote. I am citizen so I have the right to vote automatically and only thing I need to provide is some accepted ID.
Needing an ID is fine in theory, but in practice many older folks who do not drive do not have one. In order to get one you need a certified birth certificate. In order to get one of those you usually need to deal with a lot of red tape, especially if you were born at home in a rural area.
People often forget how rural the US is. Sometimes it’s hard to document exactly who you are. Especially if you were born poor and black in the South.