Most medical devices will carry out private bio-safety tests. Most electronics will perform private EMC tests. I agree it's crap but automotive is not some special case or part of a conspiracy.
A lot of regulated industries self-regulate. The regulatory bodies trust the results documented by manufacturers because they realistically have no money/time/expertise to do it themselves.
Post diesel gate "The new rules, finalized in 2018, give the Commission the right to carry out compliance checks on vehicles, order bloc-wide model recalls and slap fines of €30,000 per car on cheating producers. The EU's science wing, the Joint Research Centre, has spent €7 million on two new testing facilities that will perform snap checks, a Commission official said.". [0]
[0] https://www.politico.eu/article/new-eu-car-rules-aim-to-stop...
