Yea, from my understanding there is more Development for heavy duty diesel emissions then light duty trucks. A lot of development is occuring for Diesel oxidation catalysts, and SCR systems with urea injection(reduces NOx emissons). It’s much harder to find those components sized for your everyday truck or SUV. Although I’m guessing now that this is going to come into effect there will be a lot more focus on it.
Also from what I heard Mass. has some case going up against the supreme court trying to get the EPA to regulate greenhouse gasses.
And I was just starting to like this global warming and 55 degree days in december