This is true, but for how often Americans boil water, it’s just not worth having a dedicated device for most of them

They don’t, kettles just aren’t that much more efficient at 120v. Like a kettle will still be faster, just not by enough for people to care.

They run fine, but basically the same as a microwave, British kettles are just magic

Our electricity is 120v here in the US, so kettles take forever