In the UK, where almost everyone has an electric kettle, almost all are 3kW.
Our electric circuits aren't rated for 13A continuous draw (e.g. plug-in EV chargers should be set to 8A or 10A), but they are fine at 13A for the few minutes it takes to boil a kettle. 2.2kW kettles would be a major drain on productivity: millions of extra minutes spent every day waiting for a cup of tea!
Most electric circuits are not rated for continuous load at rated power. The US nominal 15A circuit can only supply 12A continuous. Thus heaters of all types and EV charging being limited to about 1.5kW.
You would certainly hope that selling 3kW heaters was an indication of that, and that's what I used to think, but what I've read about EV charging makes me think that it isn't.
Our electric circuits aren't rated for 13A continuous draw (e.g. plug-in EV chargers should be set to 8A or 10A), but they are fine at 13A for the few minutes it takes to boil a kettle. 2.2kW kettles would be a major drain on productivity: millions of extra minutes spent every day waiting for a cup of tea!