I lived in New Orleans in the 80s. Everyone who lived there knew these boundaries. The government didn’t want to warn the tourists out of fear that they would scare people off.
Because there was no warning, several tourists were robbed and murdered each year. These statistics were kept quiet. It was purely an economical decision.
In the French Quarter, it was best to stay on Bourbon St, and towards the river. And Canal Street until St. Pete. (Where Pat O’Brian’s Bar is). If you stayed inside that region, you were relatively safe.
That reminds me of the movie Jaws.