If a country with 220/240v electric kettles, I can believe it... but in the US the electric kettle is probably 110/120V at 12-15 amps, then I would think an induction stove kettle could be faster, no?
For the volumes often boiled in kettles, often 0.5l to 1.0l, only if you use a massively oversized pot. But then you need to account of the extra evaporation and greater cookware mass which hurts the induction stove.
Induction power is still limited by pot diameter and common cookware is very heavy for water boiling because other types of cooking need more even heat and higher temperatures.
I actually raced a 120v kettle versus and high-end induction stove to boil 1l and it was very close.
Electric kettles are very well optimized for speed and efficiency.
Your induction cooktop isn’t going to dump all of its power into a single ‘burner’, and the pot you use on an induction stove will have significantly more thermal mass than your average kettle. The heating element in an electric kettle will be directly heating the water. A induction cooktop will heat the pot first, then the pot heats the water. Lots more thermal mass to heat up.
Induction power is still limited by pot diameter and common cookware is very heavy for water boiling because other types of cooking need more even heat and higher temperatures.
I actually raced a 120v kettle versus and high-end induction stove to boil 1l and it was very close.
Electric kettles are very well optimized for speed and efficiency.