Looks like I got the last word after all! The last bit of Cox advertising that came to my house was within a few days of my last correspondence with them. That means it’s been over 2 weeks since I’ve gotten anything, which is a significant difference from multiple adverts per week. It seems they will take your name of their mailing lists if you push hard enough, so if there’s anyone else out there who’s as annoyed as I was, send them a letter. The specific email address I worked with was Phoenix.Services@cox.com, but that came to me after I filled out a form I found from the main Cox website. Since each region is set up on a different website from the others, I would suggest going that route instead if you don’t live in Arizona.
On a completely unrelated note…
That is all.