This seems to reveal that the problem with automated lights, etc. is that we no longer have a single source of truth for the state of the light or other device.

This seems to reveal that the problem with automated lights, etc. is that we no longer have a single source of truth for the state of the light or other device. I think the problem is that we are updating the state of the light but not updating the state of the UI i.e. the switch. The solution would seem to be that the automated system should be moving the switch in order to turn the light on or off instead of adding another point of control like a relay that changes the meaning of the switch position. I'm sure this would add cost to the system but I think the benefit in usability would outweigh it. The perfect system for me would be a smart switch that is electromechanically actuated by the smart system but also has an override switch that you can toggle in order to prevent the automated system from moving the switch. That way you can still maintain full control, the switch always indicates the correct state and you have all the benefits of the smart system.