The USPS is a government-run spam delivery service that there is no way to opt out of. Those of us who do banking and other administrative tasks online would be better off if the government shut it down completely, or better yet subsidized it slightly so it doesn't have to deliver spam to survive.
But as it is, I don't see any good reason to have any more respect for USPS than I do for any other spammer.
No, it’s completely different. Gmail actively tries to prevent spam. If they catch you sending it, you will be banned, and they let individual users block whoever they want. A huge part of their product is automated spam filtering.
On the other hand, spam delivery is the business model of USPS. They actively and intentionally market and sell their services to spammers, and not surprisingly, give normal users no way to opt out.
There are mail forwarding services[0] that let you automatically filter out junk mail. Yes, they cost money, but at least you can accomplish your goal of opting out (or in) from receiving postal mail from certain senders.
[0] E.g. https://www.usglobalmail.com/virtual-mailbox/
If your goal is to receive zero mail at your address, simply have all your email forwarded to this service and configure it to opt-out of all notifications.
Alternately, you can forward your mail to an entirely different address. (This is just a Gedankenexperiment; please don't spam strangers by forwarding your mail to them.)
The USPS is a government-run spam delivery service that there is no way to opt out of. Those of us who do banking and other administrative tasks online would be better off if the government shut it down completely, or better yet subsidized it slightly so it doesn't have to deliver spam to survive.
But as it is, I don't see any good reason to have any more respect for USPS than I do for any other spammer.