I just installed one of these HP spy-jet printers at a family members house this weekend. Not my idea of a good device to let onto your LAN but, 99.9% of domestic HP customers are not IT guys, tech heads or members of the EEVBlog forum. So who would have a clue

I suspect the always on internet connectivity is there for the DRM and the 'instant ink' service. Which my relation did not sign up for because they print on average one page a week. My understanding is the printer cartridges and firmware do some kind of public-private key (AES) exchange with the HP server which verifies the validity of the ink. Hence, no clones, refills or compatibles allowed. I'm sure Louis Rossmann has some rant about this? What algorithm is used to calculate how much their
open-wallet business model uses is closed source. I'm sure there is someone at HP towers who thinks this concept is the best thing since Donald J. Trump met Stormy Daniels

Security wise: What I want from [UK] ISPs is for their routers to have a separate wireless IoT interface where devices such as this printer are jailed on their own subnet. So any risk of WiFi key sharing is on the IoT and not the main domestic LAN. Routers have a rudimentary DMZ, which was how network security was done in... 1995. I can do this using OpenWRT easy, but 99.9% of HP customers are not IT guys. Cyber security? I'm sure HP can sell you that too. Instantly.