I figured it was a joke, I was just going along with it. Apple doesn't drop support, but they are constantly fixing potential vulnerabilities in iOS (security is not a wall, it is an arms race). I don't know if there was one in Airprint, but most likely that was why Apple updated the iOS end of Airprint, and it's up to the printer manufacturers to keep up with security fixes. Alternatively, Apple may have found a vulnerability in the printer's implementation of Airprint. Of course, maybe it just requires some troubleshooting. Have you tried rebooting the printer? Checking for firmware updates?
Another completely different approach is to get an app like Printopia that works on your computer as a front end to printers that don't support Airprint. I use it with my 20 year old HP6 laser printer (those old printers never die).