Well, when the government fails to adequately regulate, leaving it up to industry to self-report, this is the only foreseeable outcome - for pretty much any industry.
Greed is a massively corrupting influence.

I know that the producers don’t self-report. They’re supposed to contract with testing labs, but when there’s a lack of standardized procedures and oversight, the producers lab-shop until they find a lab that has tweaked their processes in such a way that reports favorably on even substandard goods.
In that way, the labs become facilitators of a flawed regulatory process.

The only real fix is more and better oversight (including verification of results from testing laboratories) and standardization of testing procedures.