I have been in crypto space long enough to witness large price fluctuations, and I would not be surprised if we saw - say - 4k price, however I think that going from 20k in Dec down to 1k would be too much even for bitcoin. So I am very sceptical about your prediction.

Summing up:
 - 4k - yes, we have seen such magnitudes in the past
 - 1k - no, I am sceptical