LOL, so THAT'S what regen is!
In all seriousness though, I do remember from my transportation air quality engineering class that some places were experimenting with smog units on exit ramps, that would issue a fixit ticket similar to a redlight camera. Don't think anyone actually does it though. And of course there's been talk of OBD 3 or 4 over the years that reports a CEL to an office somewhere, but that never happened either.
Ben