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All cars have to deal with the v squared air resistance, but EVs also have motors that get less efficient at higher speeds, and the more power you draw, the hotter your battery gets and that's a negative too. So really everything is aligned to punish you for going faster than a threshold speed.

With a convential vehicle, it's not so simple. A lot of things get worse, but engine efficiency is usually better with higher temperatures (which is why the VW TDI NOx emissions fix results in more CO2 emissions; NOx is a result of nitrogen in outside air being exposed to the hot engine, lowering the temperature reduces fuel efficiency and NOx production), and the gearing is designed to get maxium fuel efficiency at higher speeds. Of course, if it would be commercially acceptable, an engine and gearing could be designed to get max efficiency at a lower speed and have a 40 mph super efficient vehicle. Hybrids can do a lot better at running the engine near peak efficiency or having the engine off, allowing for higher mpg all over the speed spectrum.