If an electric car can travel 70mph and beat it's EPA range then the manufacturer did a terrible job of designing the car.
Wind resistance should be the major determining factor with an EV. Low speed regenerative breaking is such an efficient process that if your car gets bad mileage in "stop and go" traffic it's probably designed by a committee of fools.
EPA range is a defined value based on published metrics and measurement principles.
The idea that a manufacturer should under report range is a bit strange. Are there examples of ICE manufacturers under reporting their gad mileage? I doubt it.
There are two different EPA test cycles. One is more generous than the other. Manufacturers can choose which one to use.
Additionally, the cars will typically have multiple driving profiles to select between more performance or more efficiency.
Porsche, for example, uses the least generous test cycle with the most performant (least efficient) car settings. It makes their EPA numbers look bad but they are honest numbers.
An underquote is more customer friendly than an overquote.
Because you get what you pay for and then some. With fairy tale numbers you don't get what you thought you were paying for.
How many numbers do you want them to quote? For the Porsche Taycan there's a 35% difference between the performance settings and the eco settings. It also depends on the wheels you choose. Smaller wheels are more efficient.
It isn't an artificially low range number. It's the worst case number.
Wind resistance should be the major determining factor with an EV. Low speed regenerative breaking is such an efficient process that if your car gets bad mileage in "stop and go" traffic it's probably designed by a committee of fools.