Maybe we can look for historical examples of how legislation had a positive impact on a widespread harmful habit.

  Early on, the U.S. Congress adopted the Federal Cigarette Labeling and Advertising Act of 1965 and the Public Health Cigarette Smoking Act of 1969. These laws—

  * Required a health warning on cigarette packages
  * Banned cigarette advertising in the broadcasting media
  * Called for an annual report on the health consequences of smoking

https://www.cdc.gov/tobacco/data_statistics/sgr/history/inde...