This is news because it is a change from a system that has existed since its inception. And while some think noting gender identity is simply for identification when you are pulled over, the use of a drivers license for other ID checks is a stamp that says: this is who I am. 
What if we looked at it in reverse? Since inception, a drivers license has incorrectly labeled some people male or female. Owners of those licenses had to misrepresent themselves as they showed their license. If you are a male and you had a license that says you are female, how would you feel? 
So, continuing our alternative view, hasn't the story been that since licenses were established they misrepresented a portion of our society? The headline could be: "Decades Old Error Corrected".
Due to culture, many squirm when dealing with unknown gender. We need to know what the gender is of a newborn, like it makes a difference at birth.  Lack of acceptance of gender neutral is our own cultural programming.