Bitcoin is unique in that most of the traders are tied into being in one of two positions - either btc or usd. There arent a bunch of other stocks and asset classes for them to trade. They're not leaving the market. They're staying on the bitcoin exchanges with an eagle eye on the chart and soon as there is a hint of a reversal they have to all pile back in at once because if theyre on the wrong side of the market then theyre losing and wasting their time on high risk exchanges.