There are two EPA tests. Both are legal and valid. Tesla/Lucid and most of the American manufacturers use the 5-cycle test, which EPA says is more accurate (lol), and of course is better for marketing.
It’s also more expensive to run than the older 2-cycle test (which the EPA says is less accurate, lol) which is at least partly why the Germans and Koreans (and others) use it, despite it underrating mileage by a significant amount.
Both tests are just estimates, and it’s turtles all the way down.
Yes, it’s stupid af. I’d say the EPA should fix it, but they’d have to exist in any meaningful capacity to do that and not have been slaughtered by the present administration instead. But I digress.