The question is in the subject.

Are you talking about 3000 Watts versus 2000 Watts electric kettles?

He probably is and here's my guess:
Since the power is significantly higher, it might require more safety features/thicker wiring and such, so the raw materials cost rises.
Also the product can be marketed as more expensive due to the higher power = faster boiling of water.

Here in Israel, 3000W electric kettles costs 500-1000ILS, while 2000W electric kettles only costs 50-150ILS.

Some time ago there was a push to restrict the power of these kettles, as I understood the motivation came from the UK, where the grid experienced huge spikes after some TV programming just ended or had a break so a lot of people started making tea at practically exactly the same instant, creating hard time for grid management. But then UK left the EU so I don't know if that restriction finally made it into law or not.
But regardless the details, since then the power rating of commonly sold kettles got significantly reduced.

So my guess why the price difference is, the 2kW ones are the mainstream, made in huge volumes, so the economy of scale and the huge competition brings their price down. The 3kW versions are rather specialty item made with way smaller quantities just for some markets and only by some makers. And because there is limited offering, they can markup higher price for them.

@Medved: I think the EU started the restrict on the power of electric kettles. Not the UK.

The restriction was discussed on the EU, but UK was initiating it there, at that time UK was still a member. But before the process finished, UK left the EU and what I'm not sure is how that process finished, if the restriction formally passed or was dropped once the UK left the EU. And I do not know whether UK formalized that restriction in their legislation either. Either case, as makers were practically ready to transition, there was no push anymore to go back to the higher power, the power reduction solved quite a few of reliability/cost challenges (mainly the detachable base and the connector there - the contact pressure limitations by the limited near empty kettle weight do not allow to design reliable contacts for that high currents), so once such legislation activity caused customers to accept that, there is not much motivation to go back even when legislation would allow that.

For the belgian market, lower powered kettles make sense because they pay a peak usage cost for a certain time period (idk the details). For instance, if your house consumes no more than 3000w in the day, you are in a low tariff. Do you consume a peak of 6000w, you are in another tariff disk etc etc.
The folks who heat and cook electrically were majorly screwed because of that because heating always draws a metric fuckton of power.

For any other country, it does not make sense because the amount of energy needed to boil a given amount of water - obviously - is always the same. I understand wanting to flatten out peak usage but kettle use is so distributed over the morning/afternoon that it will obviously not make any difference whatsoever.

That said, i have a 2000w kettle and it is plenty fast. Within a minute i have boiling water. Theoretically i could use a traditional kettle and put it on the 3000w ring of my induction stove but that's a bit overkill.

As always, we need more engineers in government. In my country, the voters voted for a smaller government. Now there is very little technical knowledge left in government, because there are way fewer engineers and other technologically minded personnel in government. FAFO.

AFAIK the city of Almelo spent multiple times the normal cost of a street lighting installation on street lighting, because they had let go the folks from the street lighting department in an attempt to save money. Obviously, if you're gonna hire nice shiny consultancy firms to help you decide on what is the right street lighting (Rather than having knowledgeable people yourself) you're gonna spend way more. Even if that means that you gotta retain and pay your own people all year long.

Our 2000W kettles takes 6 mins to boil when they are full at the max. I heard that because 3000W kettles takes less time to boil water than 2000W kettles, they can save energy.

Actual effect is absolutely minor, probably some extra energy dissipated in house wiring, but still counted by an energy meter will offset this.