There’s quite a bit that can be done to improve the efficiency of motors and inverters. Each commutation costs a bit of energy, and minimizing that lost power (while staying within FCC limits on radiated EMF etc.) requires careful engineering.

I have a Genesis GV70e. It's intended to be sporty and not long range, so EPA is 220--if I'm driving off highway I can get closer to 280 miles. Highway I get just about 200-220. I reliably get about 3miKW averaged over the last 12k miles and at highway speeds get as much as 2.5miKW.