Clearly the logical threshold is when a single private corporation becomes the gatekeeper to your life. The internet itself is decentralized so that's fine. Mobile phones as a concept is also fine.
Obviously, the idea of "you don't have to pay to participate" has a strong legal footing, but I have to wonder if they can find a way to pivot that to "I don't have to acquire an Android/iOS device". Maybe they would develop a kiosk-mode version of the OS that will run apps tethered to a placeholder library account.
...for now, at least.
So having health care was dependent on a private third party.