I have followed all the recommended steps to remove my address from various mailing lists.
The USPS is a garbage-spamming environmental disaster that solicits money from companies to do direct marketing, offers no opt-out features, and every day drives tens of thousands of polluting vehicles to stuff unwanted paper into mailboxes across the country.
In addition to its monopoly, the post office is one of the most unpleasant retail locations anyone could imagine -- filthy counters, grudging employees, and long lines.
Since "first class" mail takes between 2-12 days, there is no reason to have first class mail delivered every day. Doing so is just a handout to the employees' unions. There may be a case to be made for more frequent delivery of expedited mail, but this would take a fraction of the number of vehicles and personell that the current system does -- and with less reliable guarantees, nearly identical prices and worse service than UPS, I always choose UPS over USPS for parcel shipment.
It's fine to be nostalgic about the pony express, but the USPS needs to either be phased out or drastically scaled down, and laws forbidding other companies to deliver standard mail must be changed.