"passively monitor the performance of a driver of a motor vehicle to accurately identify whether that driver may be impaired; and prevent or limit motor vehicle operation if an impairment is detected"
There is an OR for detecting high blood alcohol level.
There are a few years to get input, come up with preliminary rules, get more input, finalize the rules and give time for manufacturers to implement them.
This could save 10,000 lives per year and tens of billions of dollars per year.
The law says "prevent or limit operation". That is pretty broad.
If it is a breathalyzer, or a speed limiter when you are swerving over a 2 minute period, I am fine with that.
If it shuts you down for going over the speed limit for 10 seconds, or make an emergency maneuver, then I am not so happy. But that is why we have a representative form of government, and input on regulations.