There is still plenty to be gained from squeezing that last 1% out. Tesla is probably cell limited right now, so if your car is 1pct more efficient you can pull less cells in it and mthen make 1pct more vehicles.

For pure range, sure. But think about things like heat sinks or other cooling devices. Or the weight of these components themselves. Swap over to this new SiC, you get more direct efficiency, AND you don't need to carry as much supporting hardware!

EVs tend to be efficient at high power. They can be 94-98 percent efficient at 100kW but normal driving is something like 4kW at 45mph.

If you reduce loads by 40 to 50 watts, you can gain a mile of range. With inverter losses in the 1-2 kilowatt range at high power there is room for improvement.