Hey, it works for what it's meant to do (give quick info) ... so what's so bad about that?
Because it's using a unit defined for motion/speed and applying it to capacity, for which a measure (kWh) already exists. On top of that, it's simply inaccurate as range changes based on myriad factors already discussed. The proper unit, kWh, does not vary in accuracy, just like gallons or litres.
I stand by the fact that it is ridiculously clumsy and over-complicates something by trying to make it simpler; dumbing it down.
It's the equivalent of gas pumps giving you a rough measure of potential range based on what you are driving, rather than gallons or litres being put in the tank. But you are still billed based on a rate for gallons or litres and can just look at your estimated range on your display if you wanted that rough idea after the fact.
If you saw the example charger I showed, it quite clearly showed kW as the rate of charge and kWh as the volume. Perfectly logical and exactly what I'd expect. The kWh component and cost are the same as your gallons and cost on a traditional fuel pump. Nobody is going to have a hard time quickly wrapping their heard around that. This seems like an answer to a question nobody asked and that's why I'm taking such a strong issue with it. Let people learn kWh, it's going to help them out in a future that's looking to be more and more electrified.
And somewhat of a tangent here, but this, electrical illiteracy, is a huge impediment in having a well-based discussion about electricity systems. People don't understand what means what and even journalists are notorious for misrepresenting output (kW/MW/GW) as output capacity (kWh/MWh/GWh/TWh). I had a great dialogue with a woman who lived near an Ontario wind farm and just assumed that if they were spinning, they were making their rated capacity. It was difficult to bring her down to earth and explain that nameplate capacity does not equal actual output and that just because a wind turbine is rated for 3MW doesn't mean it's equivalent to a hydro-electric dam of the same capacity, nor does 900MW of wind compare to 900MW of nuclear or gas. This brought us around to output capacity, capacity factor...etc. This is all stuff she thanked me for explaining. Just think how much better informed consumers would be on these topics if they already had a fundamental understanding of the units because they interact with them every day like gallons or litres?
As I said earlier, the answer is never less knowledge.