When I was in China at airport you could see that Youtube, Facebook, WhatsUp, Viber, and even Google are forbidden.
I am curious to know what China says about that?
The ban is political and China's response is political.
But what they are getting at, perhaps not unreasonably, is that it looks like all these apps were banned because they are by Chinese companies, which may be discriminatory under WTO rules.
This is not what China does. China, like other countries, blocks specific websites and apps because of their contents or functionality, not because of their origin (at least if they do they tend to be smart enough to be subtle about it...)
I don't think WTO rules say anything about what websites or apps a country should allow but rather the rules are about preventing discrimination between trading partners. So my understanding is that a country is essentially free to ban an app because they don't like what they app does but they are not free to ban an app because they don't like the country it comes from.
Hey, you're a good HN user; anyone who posts things like https://news.ycombinator.com/item?id=16197431 is fine with us. But you simply can't post things like the GP comment, regardless of how right you are or feel about the underlying issues. That's not so hard to understand, and the vast majority of the community here would agree. We're simply trying to prevent this forum from destroying itself in the way internet forums traditionally do.