it is mostly because of the bitcoin-ban-FUD that is being spread all over the internet combined with whales dumping on the exchanges. the ground work is also there with the bubble crap they have been spreading all these past weeks and with the stupidly high fees people don't believe in bitcoin anymore.
this is crazy
this part is not crazy, every time bitcoin drops, altcoins drop like this. even more than bitcoin. don't ask me why, all i know is that it happens every time without a doubt.
What happen with bitcoin right now is just plainly slightly down in market price probably people are selling their bitcoins because they are slightly confuse and also, the fork does not achieve majority consensus causing the drop in price. Lastly, I do believe bitcoin will regain back its price soon.