That's not how the GPL works. If it would be inconvenient for BMW to incorporate GPL software and properly comply with the license by providing source, then their only alternative is not to incorporate the GPL software. Full stop. Harm or proprietary hardware has no bearing on the rights granted by the GPL.
That is true in the real world if and only if there is someone willing to sue BMW and see it through to the end. Absent someone doing that I don't see how the GPL is actually enforceable. In some ways it is similar to what we have with surveillance and the NSA in US. While they are probably breaking the law the courts have been unwilling to force them to stop.
》 That is true in the real world if and only if there is someone willing to sue BMW and see it through to the end. Absent someone doing that I don't see how the GPL is actually enforceable.
So... just like every other contract, ever? You can't have an enforceable agreement between civilians without courts. Anyone willfully making a derivative of GPL software explicitly agrees to that contract and as usual, courts are the arbiters. Yes someone needs to go to court.