I have measured it. I have to change my coffee preparation technique depending on the stove.

On resistive or radiant electric stoves, I turn the heat on under the kettle, then grind the coffee add the filter. The water reaches a boil in about the time it takes to do those tasks.

With induction I have to turn on the stove last because its just too fast.

Gas is by far the worst and involves waiting around for minutes for the water to get anywhere close to temperature.

I measured my water on a scale, and timed how long it took for to boil water for my morning coffee. Same water, same kettle. It was a while back, but as I recall it was around 8m to boil on gas, about 4m to boil on electric. Resistive or radiant made no noticeable difference, and induction took around 2m.