For anyone who gets this abhorrent soft brick on their Roku TV, MAC address filter your TV on your router (prevents it from accessing the internet and phoning home). Hard restart your TV (unplug and replug since they lock you out of restarting via GUI), and Bob’s your uncle (dumb TV with no forced agreement for continued “dumb” use).

Unclear how long this will last, but as long as you keep your TV off the internet you should be good to go.