Reuters published an article about a proposed class action lawsuit in California over range of Tesla cars. No author named. CNBC picked it up. It's so dumb! Are all gasoline car manufacturers quaking in their boots at the prospect of the same lawsuits? It's going to boil down to this: if you drive your car like it is being tested by the EPA - slowly and gently, dry conditions, level ground etc. etc. - you will get the range figure. If you drive it the way we normally drive cars, or even faster, in rain, or up a hill... you will get less range. Also, water is wet.
However the end fate of this proposed lawsuit will get no media coverage
I concur that Tesla has really just used the available EPA rating rules appropriately and completely legally....and those systems are actually what is apparently confusing people who don't bother to understand what they mean. In my opinion, EV range should be advertised with a "Typical" range defined by something like charging to 90% and driving down to 10%. So, just give people the 80% estimate, and a big note saying: "Weather, terrain, load, driving style, vehicle modifications, and many other factors may increase or decrease the available range. Physics is real and is good to understand."
The EPA EV range is generally based on using 100% of the accessible battery capacity, of a new vehicle. Nobody should even expect to use 100% of the range of a new car -- it isn't "real world" at all to expect to achieve the number of miles defined by charging to 100% and driving the car until it can't go any farther. Nobody drives a gas car hoping to run out of gas just as they pull up to a pump.
Another part of it is that people just don't understand math or what the EPA numbers mean. The EPA MPG or EV range rating is based on averaging 55% city/"stop and go" test results and 45% highway test results. And of course those tests aren't actually real world. And even the highway results have a lot of lower-speed driving as part of the test.
In an ICE car, driven carefully at not-too-fast highway speeds, I've always found it pretty easy to exceed EPA average MPG, because you eliminate all the city driving that is inefficient for an ICE. If you drive a lot of short, city trips, and ICE MPG falls to the floor. It all makes sense.
In many EV's, the city driving is more efficient than highway. I think I recall seeing several years ago Model S range records where they drove at 27 miles per hour and got ~600 miles out of it. But on the other hand, drive at only highway speeds and the range should be expected to be lower than the EPA average rating. Drive exclusively at fast highway speeds, and range will drop further.
And the Government/EPA website even illustrates part of this effect for those who care to actually use it -- you can actually "Personalize" the FuelEconomy.gov data with your own percent of stop and go vs. highway driving, and get the correspoding range estimates. For example:
I'm not sure why the Model X range estimate goes away for the 100% and 0% versions...but anybody that can internet can see that even within the EPA test parameters, Model 3, Model Y, and Model S range varies by 23-32 miles just by toggling that one variable. It is quite logical that driving well outside the parameters of the test will increase this variation....and potentially in either direction. You can drive at 27 miles per hour with the AC off to go 600 miles, or you can drive at 90 mph with the windows open and the heat blasting in the winter to drastically reduce your range. It is physics, not Tesla being deceptive.