People ignore the fact that an ICE is also less efficient in winter and that it usually needs to sit stationary with the engine running just to clear the screen, while most EVs can preheat so it’s already warm when you get in.
EV drivers on this thread seem to be reporting a drop in range of between 15 and 30%. Of the last half a dozen ICE cars I’ve had I’d say that the average drop in the coldest months has been around 5% with the worst being 10%. Some difference. Even in these freezing temperatures I’m still getting 550 miles range and on longer journeys it creeps back up towards my normal 600 miles plus. I keep my car in my garage so never need to warm it up or defrost it. I just get in and drive off and I can feel the heat from the seats before I even get to the end of the road, so I don’t think I’d bother with preheating even if I had it!