The only one showing any lack of social intelligence is you. The author is choosing not to go into unnecessary personal details while giving a short back story as to why they did a thing.
I've thought of doing basically something similar so my wife knows I'm in a position not to be disturbed. I can, and do, tell her when I have a scheduled call, but unscheduled calls do just happen. Something like this would let her know I can't be disturbed without her coming in, asking and then going 'oh shit, sorry.'
In no way is it engineering a way out of dealing with my wife.
The nice thing about boundaries is you are not required to explain yourself. "Hey, please don't interrupt me between 9:00 AM and 5:00 PM, unless it is an emergency. I need to get work done, and interruptions break my concentration. Thank you for understanding." You also don't need to build complicated devices.
I've thought of doing basically something similar so my wife knows I'm in a position not to be disturbed. I can, and do, tell her when I have a scheduled call, but unscheduled calls do just happen. Something like this would let her know I can't be disturbed without her coming in, asking and then going 'oh shit, sorry.'
In no way is it engineering a way out of dealing with my wife.