All these guys who have thousands of Bitcoin who sell during a large movement like this aren't stupid - they're selling for a reason and they know what they are doing.
The reason is they know they will be able to buy it back cheaper.
Selling in order to buy back cheaper isn't stupid, I agree. It's only stupid to think making the initial ask is a risk-free strategy. It is not:
it is a wager that the price will fall. Needless to say, short selling is an even bigger wager that the price will fall...
Those who are truly confidently bearish on bitcoin (or any commodity/stock) will short sell as hard as possible, given the slightest opportunity. Right?