For what it’s worth, you can sign-up through DMAChoice to stop receiving junk mail [1]. It takes a few months after you sign up to really take effect, but it has easily eliminated 90% of the mail I used to receive. Well worth it IMO for the $2 fee every 10 years.
Title 39, United States Code, Section 3008 authorizes the Postal Service™ to issue a prohibitory order against a mailer who sends you an advertisement offering to sell any matter that you, in your own discretion, believe to be “erotically arousing or sexually provocative.” You can request the order by completing the relevant portion of PS Form 1500, Application for Listing and/or Prohibitory Order, and submitting it to any Post Office™. The form is available at your local Post Office. Thirty days after receiving the order, the mailer is prohibited from sending you any further mail. Violating this prohibition makes the mailer subject to court enforcement action by the United States Government.
I'll take your word for it that it works, but I would have been skeptical. Am I correct in understanding that they essentially function is a communication medium with the companies maintaining these unsolicited mailing lists, and those companies voluntarily remove people that pay DMAchoice?
https://www.dmachoice.org/register.php