That's some advanced gatekeeping right there. Where other appliances might have a blink code or several digit error display (Miele) to look up in a manual, the phone method tires you to the manufacturer.
The support hotline will ask you to hold your phone towards the device. It is less error-prone (than a human) and contains more info than a blink code. I find it really clever.
All the same diagnostics you can do at the machine, the phone home service allowed a remote engineer to diagnose as well. Things like drum rpm, tilt/knock sensors, uneven balance detection. Instead of paying a human $250 to come out and press buttons, they can do it remotely.
I understand in the pessimistic age of John Deere, all remote diagnostics are bad, but that is not the case here. I was able to do all of the diagnosis myself to determine it was a bad stator and then replace it myself.