Neglecting clothes for a few minutes, your body both radiates heat and absorbs it. When you are in thermal equilibrium you feel warm. If your walls and roof had low grade radiant heaters on them and emitted enough infrared to balance your own outgoing radiation, you’d be warm, even if the air temperature was cold and you had no clothes on.
So if you covered your ceiling with cheap thin iron sheet metal and built small induction coils behind them and heated the ceiling instantly, you could instantly feel warm in a cool room. Exit the room and you turn everything off…letting it lose its tiny amount of heat.
So proper system design could let you have low latency zone heating. Since you usually don’t use all the rooms in your house at the same time, there ought to be more than 50% efficiency in that sort of a system.
2. Our current approach of heating the whole house through forced air is much less satisfying than having a concentrated heat source (like a fireplace) that you can just walk towards and get as much heat as you want out of. Maybe psychological factors might play in…if you “could” be warm with just a little bit of effort maybe you won’t mind being colder than normal. Maybe heat gradients are better for you than uniformly high heat.