>But with induction stoves becoming the norm for new kitchens (at least around here), all you need is a suitable, passive kettle instead of the kettle+base.

One of the nice features of any modern kettle is that it automatically and audibly shuts off after the water starts boiling, so you know your water is ready and you don't forget and get a burnt kettle from leaving it boiling for an hour. You won't get that with a passive induction kettle.