Toxic emissions have absolutely not gone down to zero. High respiration activities next to a highway still get you a solid dose of toxic stuff. Yes, it would be much worse with 1970s vehicles but it would be much better if the majority of vehicles sold today would not be able to use the regulatory SUV/truck loophole to be able to pollute more. This loophole is not just about CO2.
I witnessed myself what a huge impact on air quality it had on a street to see heavy two lane traffic gone and that had nothing to do with CO2 and it was even without that loophole you have in the US.
Toxic emissions have absolutely not gone down to zero. High respiration activities next to a highway still get you a solid dose of toxic stuff. Yes, it would be much worse with 1970s vehicles but it would be much better if the majority of vehicles sold today would not be able to use the regulatory SUV/truck loophole to be able to pollute more. This loophole is not just about CO2.
I witnessed myself what a huge impact on air quality it had on a street to see heavy two lane traffic gone and that had nothing to do with CO2 and it was even without that loophole you have in the US.