Earlier quoted context omitted.
Not all of the bans are the same. You might be referring to the ban that was announced late 2015 (IIRC) which was a temporary ban for a year to see if it works.
Meh, they do this a lot. Every year they talk about how coal will be banned in Beijing next year, or that they'll stop harvesting organs from condemned prisoners, and so on. Just for them to repeat the same pledge next year. The Chinese gov promises arent credible, and something isn't a sure thing until they really do it.
It's a first step. I think that this is slightly different from either of those because
a.) the money in this industry and the number of people depending on it is only a fraction of those of coal mining
b.) people will never need ivory the same way they need organs
Even though they do have a long way to go, promising that they will do something about it is the first step.