Cars are regulated to high heaven. They don't regulate software quality because the unholy union of big business and government that is the current US auto sector and its regulators have yet to find a way or need to do so that benefits them.
If it only impacted automakers they might do it. However if you apply this standard to cars you will have to apply it to a lot of other sectors. After all why stop at car makers. Why should other appliances not get the same treatment like IoT as well? A lot of other companies would hate to have this standard applied to them hence they lobby against it as well.
