American outlet electricity, I recall, is such that it is actually some kind of weak. You guys need the microwave because your kettles aren't getting enough to eat, so they can't lift.
There was a technology connections video of that I think...
TL:DW Even in the US with its 120V electrical system the kettle is faster than gas or electric stove kettle (he didn't test microwave) but most people just don't drink tea often enough to warrant a separate appliance for it. He does go into the whole microwaving water in a follow up video here: https://youtube.com/watch?v=RpoXFk-ixZc