Old, old news
This tech has been around since the 80s and is very reliable. There might be a few reasons it hasn't been installed in cars as a standard feature, though: to be useful, it should err on the side of caution, so those trying to operate vehicles with it installed should expect false positives. There might be some concerns over hygiene with the breathalyzer version for shared vehicles unless mouthpieces can be interchanged. The current approach is to have an enforced time-out period after a few failures which can leave drivers stranded if things aren't working quite right for whatever reason. Finally, with the current deplorable efforts by insurance companies to invade the last vestiges of our privacy how far behind will rate increases be for those who don't have their cars retrofitted with this tech if it becomes standard in new vehicles?
Biting the hand that feeds IT
