My understanding is that this test is a new one. Typically they only did it on the drivers side of the car and not the passenger side. Its quite normal for US manufactorers to only implement safety equipment to pass the tests. So the next generation of US cars will likely pass this test, since they have already implemented these safety measures on the drivers side of the car. It's just a case of copy pasting it to the passenger side of the car. I imagine the main reason for this is that US car brands rarely export to RHD markets. While most Japanese and European brands sell their cars in both LHD and RHD configurations. Therefore they need to pass these tests on both sides of the car while typically US brands would not. They probably still cost optimise per market, but the chassis will be inherently stronger on the passenger side because of this, even if they do leave off a few components. Chrysler had this issue when they brought the grand voyager to the UK, they didn't update the chassis designs and as such it received very low safety ratings because of how weak the drivers side of the car was in a frontal impact. Ford also decided not to fit safety systems to the European Mustang because they didn't think Euro Ncap would bother to test it. So they didn't fit simple things like seat belt pretensioners to the rear seats, whereas the US model had them. European cars (in the US) tend to do well, simply because they tend to be more expensive and premium vehicles. They can justify spending a bit more on this type of stuff, rather than the bare minimum to be able to advertise to consumers that their car passes the tests (barely). Of course most domestic market EU cars, will be somewhat similar to US ones, since they are made to be cheap, but with the advantage of being made for both LHD and RHD roads.