When someone is texting they aren't looking ahead, so headlights on are not going to help.
How can you not see a car coming at you. And if there was, the headlights are not the issue, the person in the car is.
Am I missing something about how the headlamps make a car visible to someone. If 2 cars hit head on, headlamps were not going to help at all. If you can't see a car 200 feet or even 100 feet in front of you (either way) then there is some other issue going on where headlamps or DRL's would not have been a factor. If you can't swerve at that distance then it's either distracted driving or a medical issue.
Headlights on are just a way to make you feel all safe and cozy in your vehicle, when in fact the accident will be unavoidable.