As I understand it, there was a time when people would buy expensive luxury European cars in their countries of manufacture, and import them for their own use,

As I understand it, there was a time when people would buy expensive luxury European cars in their countries of manufacture, and import them for their own use, which cut out the local wing of the manufacturer, local dealers, etc. This probably offered a broader range of models and options and may also have saved money. They could care less about the 25-year-old cars-- it's the new ones, the ones that probably meet or exceed the spirit of US safety standards but have some marginal differences from US norms or lack a formal certification, that they're after. They probably offered the 25 year carveout to make sure they could get the restriction on the important commercial market without creating a dispute with a niche community (the vintage-car enthusiasts) that could derail the whole regulatory process. To me, the equally weird part is the car-of-Thesus situation. We have a regulatory environment that says basically "here's a block of rust that was demolished in an accident and sat for 25 years in the rain in a scrapyard, but because it has the VIN plate from an ancient Mustang/Defender/Porsche/etc. on it, you can build basically an entirely new car around it and not have to honour modern rules about safety or emissions." There isn't an obvious way to incentivize the classic-car people to think in terms of those standards when they retrofit.