1. Which one? A US 1000-1500 watt kettle? Or a UK/EU 230V/2500W unit?
2. Its a bit beyond the scope of this discussion, but UK domestic electrics make use of something called a ring main, which I don't think is used in the US. All of the outlets are on a ring that connects to the panel at each end. It means you can draw much higher currents before exceeding the rating of the conductors. Plus they switched a while ago to metric conductor numbers, so no more AWG/SWG.
3. It only exists because the current needs at 120V get a bit impractical once you have larger appliances (Kettles being an odd cultural outlier), like washing machines or driers.
And you misunderstand the fuse thing. Its not a fuse in every outlet (outlets do not have fuses, in fact because of the ring main, a whole rooms outlets will be on a single fuse (sized to protect the wiring in the walls only).
There is a fuse in PLUGS. Sized depending on the device attached to the plug. So a table lamp might have a 1A fuse (or smaller if you can get one). This makes it highly unlikely that you will exceed the rating of the devices cable before the fuse fails.
Its not perfect, but its substantially safer than the US system. You have the smallest fuse possible protecting every single device.
And the outlet thing is both cultural, cost based and stupid. But even then, the power strips still have real fuses in every device.
There is also mandated annual testing of electrical appliances in any workplace (which is something I did a decade or so ago).