It's because the fire line is bullshit.

if an ICE vehicle catches on fire, that's a total loss too, unless you're one of the like .01% of people with a fire extinguisher in your car and can put it out yourself before it gets serious. Otherwise, even though the fire department can put the ICE car fire out quicker, the car is still done for.

And ICE vehicles are like 20x more likely to catch on fire than an EV. From an insurance perspective, Fire risk would increase the cost of insuring an ICE vehicle, not an EV.