I think that the intent of the bill was to cut down on police corruption. To discourage police from extorting small time users.
In part, I think this because it was mentioned it the couple of articles that I read about it.
So, it doesn't seem to be directed at any of the targets people in this thread have said it won't achieve. Instead it seems to be directed at a form of police corruption. I am just going by what the Mexicans said. So I may be way off.
All imho, ymmv.