The code reader trick is a toss up. Many emmissions related codes that put the truck into reduced speed or idle only mode require on-board tests to be performed and pass before they will allow the limiting condition to be cleared and you'll still be dead in water until its diagnosed, fixed and the proper prove out test is run.
Making all that crap fall off is the best answer, but thats not a cheap proposition these days either.
The fact that the EPA can Mandate a vehicle shut it self down because of a failure in an emmissions control system, that they also mandated is such massive government overreach. Unfortunately I think reversal of such overreach will take an act of congress and lord knows thats got a snow balls chance in hell at best.
But who knows. Removing supressors from the NFA list and repealing ridiculous emissions standards that have made vehicle so much more expensive and less reliable are certainly things I think at least a small majority if Americans would be all for. Maybe some folks in DC will actually bring that stuff to the table with valid effort and planning behind it. I wont be holding my breath.
Cant wait to see how these new Gas Particulate filters pan out and what kind of nonsense problems they create.