I dunno, tons of people I know in the US have electric kettles. Its not like its incredibly painful to use them, and they'll still usually beat out using the microwave to heat water quickly, but only slightly. While it is about half as much power than most of Europe, its still only a few minutes to go from tap water to boiling. It is not like we're talking hours to get it to boil.

From my experience one of the biggest reasons why people don't have an electric kettle is because they often don't think they have a use for them. Tons of people in the US would really only use it for making coffee, of which drip coffee makers were incredibly popular for a long time. So needing fast hot water is somewhat rare, and usually when its needed in regards to cooking you can just measure your water in a measuring cup and microwave it for a couple of minutes which is just about as fast.

The people I know who actually use electric kettles in the US are:

* Those who brew a lot of tea (far less common in US than globally)

* Those who often do alternative coffee brewing methods (pour over, french press, aeropress, etc)

* Those who make a lot of ramen or other instant noodles and have limited kitchen spaces (college students)