Well, sure, if auto purchasers were at risk of massive fines if they received a vehicle where the manufacturer had done something that the average user wouldn't have the skill to detect, no one subject to the government imposing such fines would ever buy a car again, which would solve the problem quite completely.

OTOH, destroying the entire auto industry in the subject jurisdiction might not be considered an optimal means of resolving the problem. (And, indeed, might be so suboptimal to the population as to have catastrophic political consequences for the government imposing it.)

I'm not sure if you are satirical.

How would fining the end users solve the problem?

Because no one will ever buy a VW again, and so other carmakers will take note.

And people will be on the hook for $20,000 because they purchased something from a now-nonexistent company?

That's idiotic.

Would anyone buy any vehicle ever again, given the possibility of a 20k liability for something out of their control?

This position has not been thought through.