Simply because the lack of Chinese bag holders to buy and hold our bags.
every day 2k of bitcoin created, who is going to buy them?
huge amount of bitcoins gonna be sold by Chinese, no one can buy them and hold the price above $2k, in fact, not even $1k.
China is not the only player in the bitcoin market. They are a very big market but if you look at volume you'll see that markets with fees Korea and US based exchanges are far far in front of Chinese exchanges.
A flash crash could be likely if this current rise in price turned out to be a bull trap.
Either way, i don't think that the bullishness that we've seen in the past few months can be sustained any longer. We're reaching a tipping point, and i think price will go to less than $3k and stay there, if not even less than that.