alt Hacker NewsAll of the other examples you gave are products constrained by physical reality with a small set of countable use-cases. I don't think computer operating systems are simply mature appliance-like products that have been optimized down their current design. I think there is a lot of potential that hasn't been realized because the very few players in the operating system space have been been hill-climbing towards a local maxima set by path dependence 40 years ago.
To be precise, we're talking about "Desktop Computers" and not the more generic "information appliances".
For example, we're not remotely close to having a standardized "watch form-factor" appliance interface.
Physical reality is always a constraint. In this case, keyboard+display+speaker+mouse+arms-length-proximity+stationary. If you add/remove/alter _any_ of those 6 constraints, then there's plenty of room for innovation, but those constraints _define_ a desktop computer.