For the induction cooktop, there's circuitry to drive the induction system, which then creates magnetic fields, which then interacts with the metal pot, which gets hot and heats the water on one side while radiating heat into the air on the other. There's a lot of stages for losses here.

On an electric kettle, there's just a heating element, often directly bathed in the hot water.

There's absolutely less losses with the electric kettle, so for a 3kW kettle and a 3kW induction cooktop the kettle is slightly more efficient. Slightly.

The contact surface of the pot is much larger, though, I'd expect. It's also not localized.