I agree with you, but I understand the thinking behind the OEM thing.

The OEMs have deep pockets & lots to lose if their products fail early. Aftermarket manufacturers tend to not have so much to lose.

Granted the bi-annual inspection would catch the failed products fairly quickly, but how many lawsuits will CARB have to deal with when all those "CARB approved" aftermarket products need to be replaced after a year or two & there is no manufacturer to go after?

It's a CYA game, short & simple.