Most likely Tesla shreholders shorting caused this market dip.
Tesla's tweet cause a lot of short sellers to lose millions in USD.
Most likely these short sellers of Tesla also are techies who bought into BTC a while ago.
They most likely cashed out of BTC and other cryptos to cover their losses.
Possible explanation.
I like that theory, there might be their own SEC investigation there as truly unusual stuff was happening, not in the stock market its a risky venture if u think crypto is not risk already...