The ICO ban hit two birds with one dirty Chinese rock. First, buy reining in the ICOs, they stopped the affluent Chinese from using these to get money out of the country (capital flight).
Second, the resulting price collapse allows the government to buy bit coins for cheap. It would be close to impossible that the gov't of the country mining bit coin would not want their share of it.
The China ban is for one simple reason - create a massive amount of FUD, lower prices globally and buy in after the price crashes far below what it is now.
See, China does this on a regular basis with their own fiat currency. They manipulate it like no one else and make huge money off of it. Trump talked a lot about this in the lead up to the 2016 election.
I've never thought that I could think Trump was right about something, maybe this time Trump was right about China talks.
All China does is spreading fud about something that they can't afford. And create a chaos.
At least with regards about currency manipulation, Trump had it right. People have been saying this about China for decades, that they are devaluing their currency to keep export prices low. It's just that no presidential candidate or president has been this vocal about it.