The average Crypto currency speculator does not understand the technical difference between Bitcoin and Bitcoin Cash.
But the common speculator knows that in an elephant fight the rat must flee when one hears Jihan Wu. Roger Ver Vs The guy who think that is satoshi AKA Faketoshi, people know that nothing good can come out of something coming from these guys, and faketoshi made threat on twitter. unfortunately this only shows that still is too early for cryptos to be used as a means of payment and mass adoption, imagine how the sellers would be in the constant fight that exists in the crypto world?
They read in mainstream media about a Bitcoin war and they think it is happening in Bitcoin
People know that faketoshi and Wu have bitcoins that could sell and make the price of bitcoin fall
While I know that there is a confusion between Bitcoin and BCash and while I have no idea what triggered such a dump (aside of the usual market manipulation)
People are afraid