Different pollution, not necessarily more. Tuning the engine for more fuel efficiency generates more nitrogen oxides (above the legal limit in this case) and less carbon dioxide.

That's a fair nitpick, but my reply to the parent comment still stands - that the regulation was about pollution, and not engine performance.

Your flaw is the assumption that all, or even most, customers prefer the non-tangible idea of "reducing pollution" to the tangible experience of greater performance.

>> non-tangible idea of "reducing pollution"

That's exactly the problem with the public's understanding of pollution [1]. If they can't see people dying in front of their eyes, they won't believe it...

[1] https://www.theguardian.com/environment/2021/feb/09/fossil-f...

Right, and many customers would prefer the performance, thank you very much.

Yeah, but most of us -- even enthusiasts -- aren't cutting off their cats to do so.