i wouldn't call that a "drop below $1000" because obviously it didn't last at all. and also because it was a one time big sell off that ate through the orderbook and that will always happen when someone sells a big chunck of bitcoin or anything else in any market at once.
the important thing was the come back that only took less than a minute to complete and price came back up to $1150 in matter of minutes.
It wasn't that people themselves dumped the price down to below $1000 levels. It was more the result of stop loss order triggering each other, where you see a short lasting deep red candle. I am quite sure that a wealthy entity has done that on purpose. Especially when you also take the massive green candle that resulted in a peak at +$1350 levels into consideration. It's a way to eliminate the "competition" (often referred to as small fishes).