CARB needs to be Gitmo’d.
Or the LA Basin needs to be depopulated by 1000x.
Indeed many car can be made to run cleaner then CARB specs but they won’t except them because they have after market products on them to do so.
I know that for a fact it happened to me had a car that passed smog test and refitted it and the emissions were lower.
Changed items Intake carb headers with air pump fittings