Bitcoin whales number has hit ATH, price went up so fast to $19k and suddenly dropped by 16% today without any rational reason with huge liquidations happened on exchanges. Does anybody else see a conspirasy theory here or it's all pure coincidence?
Since when are markets rational?

Uptrends don't play out at a linear rate, especially with BTC because the market is so illiquid. Short squeezes and FOMO cause irrationally fast spikes to the upside. Long squeezes and panic selling into a thin bid side causes the same thing in the opposite direction.
I wouldn't call this a coincidence. It's just how markets work.