In my opinion, the technical side of the problem is much scarier than the moral one. The people trusted with the power to turn off washing machines probably will not abuse it to the point of causing too much damage (except someone will not be able to do the laundry on time, once), but ransomware will become much more interesting. 2084: "Who controls the washing machines of the nation, controls its future." Will the people implementing the system be able to allocate Space Program levels of attention to its safety and security? How do we ensure it's not like another IoT system to fail because of insufficient key strength / Turing-complete on-wire format fed to vulnerable parser / logic errors in authentication flow / Tech Company A deciding to stop supporting a critical dependency? I don't think it's impossible, but it's a hard programming and managerial problem.