Disabling alertness sensors might worsen drunk driving actually.
Enforcement is abysmal for stupid reasons. Courts are reluctant to remove the ability for people to drive because America purposely made itself dependent on cars, and cops are reluctant to actually arrest a lot of people for drunk driving because they tend to be buddies, or worse. You can find plentiful examples of off duty officers trying to get out of drunk driving simply by being a cop.
This is what you get when you can vote on the sheriff and judges who insist they are "Tough on crime" because they sentence a dude smoking a joint to years in the joint while ignoring real problems like, you know, murder and theft and violence and all the shit their buddies are doing. The "Tough on crime" people are the ones drunk driving often enough.