I exempted kitchen appliances, and suppose laundry too. Sometimes these are on 220 which is a different circuit already, right? Everything else in our place needs to be converted to DC.
Edit: can't reply, so added below:
Our lighting has been LED for a decade. USB PD up to 240W handles most of the other issues you mention. I have a USB Fan at my desk. I think the issues are solvable if one is motivated. ;-)
Why? Which DC voltage? The low voltage that use now is too low voltage for running in the walls. You're going to need converter boxes; DC-DC converters are more efficient but you are going to have wall warts everywhere. Also, USB-C is not enough power for things like TVs.
Plus, I have a bunch of things like fans and lamps that need AC. So now going to have converter boxes from AC toDC.
Also, appliances are where all the efficiency gains are because that is where all the power goes.
Edit: can't reply, so added below:
Our lighting has been LED for a decade. USB PD up to 240W handles most of the other issues you mention. I have a USB Fan at my desk. I think the issues are solvable if one is motivated. ;-)