Don't forget that most of the exchanges are still closed. What will happen when new investors/traders can sign up and find the BTC at the lowest point in the last few months?

Maybe that can be a reason, many big exchanges closed the doors for new customers. Today is the black day, bitcoin and alts are going down and everything is red, not even a single coins is green today, I think this can be a bottom now, or its very close. This downward trend will end soon, and we can see price rising after this storm. Who has pairs with fiat and sold yesterday or before is in profit and they wait good entry point to return in trades, now is the time for buying if you have dollars or euros or any fiat you have, hold bitcoins and alts you have.
This trend can be a great opportunity to buy more now, hold them till it arise, know that panicking sometimes leads to more dissapointment soon, so better hold and don't let yourself lose more.