there are laws which require the use of mail. ie first class mail, or certified mail.
Yeah there a laws about who is eligible to become POTUS too but.................
Yeah, and there are immigration laws and borders, yet the same government that runs U.S. Post Office, is aiding and abetting a violent invasion of our country by Mexico, all while forcing the law abiding tax payers to subsidize the governments country killing open border polices.
So I would guess the law you cited is *absolutely* meaningless.
Not as many as there used to be, although there are still some.