It is illogical to assume that since bitcoins has depreciated to this price within the last 6 months, by the next 6 months it will decline to less than 1000 usd. The market don't work that way.
I do not think Bitcoin can fall below $ 4,000 because its value is much higher. Although Bitcoin and cryptocurrency are facing a lot of difficulties in the current time, the long-term potential is very large so investors should not be too worried because of the fluctuations in this time of the market.