I wonder what this would look like: for things like routers, you could display a private root in something like a QR code in the documentation and then have some kind of protocol for only trusting that root when connecting to the router and have the router continuously rotate the keys it presents.

Yeah, what they'll do is put a QR code on the bottom, and it'll direct you to the app store where they want you to pay them $5 so they can permanently connect to your router and gather data from it. Oh, and they'll let you set up your WiFi password, I guess.

That's their "solution".