Or how about my 11" cast iron; the induction only heats the middle 7". Half the pan is useless.
As for your cast iron maybe use the correctly sized induction element then? It’s cast iron and it doesn’t spread heat well, that’s how it works. You would have the same issue on a resistive element.
They make induction cooktops for woks (they are basically slightly bowl shaped), I’m not sure how popular they are in Asia, however.
Ikea has the 36" in stock in the US for 950USD, but the 30" would be tolerable at 800 or 700USD if they were available.
The side burner of a $150 grill does a fine job, but can't find a wider-diameter induction.
In a home context its irrelevant. You're not doing true wok cooking at home anyway, your piddly little small bore home gas feed won't be providing anywhere near the required intensity.
As I said watch the video it says it better then I
Doing a super low temp simmer on gas is hard. Double boilers are only something you need with gas. Induction imho and experience is just better all around. What the video for someone putting it far more eloquently then I ever could.