I am not sure but maybe the MyEtherwallet scam has led to some people dumping their ether out of fear, that caused the drop in ether, and this together with the anticipated coin split may have had a negative impact on the other coins
It's a domino effect and everything went falling that's why all coins are being dumped and bitcoin is included to it with the upcoming August 1 split. Crypto market is changing nowadays and I don't think it's going to take any time longer from now. Though I sold some bitcoins already for some profits as I need cash.