Amazon did lock the guys account for the report from their driver. That did lock him out of his other IoT devices.
There are other doorbell choices, like Eufy by Anker. The one this man used.
An example that comes to mind is how if you get banned from Steam, you typically still retain the ability to access your past purchases, you just lose multiplayer, purchasing new content etc.
Similarly, companies should not be able to unilaterally discard the responsibilities they take on when they sell people things that require continuous service to operate.
This should be especially relevant in cases like with Philips Hue, now that they've chosen to bear the burden of even previous Hue owners' smart homes, they should not be able to willy nilly shed that in a way that renders the system non-functional. Any bans they make should just leave the hardware usable in the way that it already was.