Very surprising to hear that despite all his experience and expertise, he dumped the coins when the prices were very low. Would have made sense if some teenager was doing this with his pocket money. I guess he was hard pressed for funds and therefore made this move. Imagine what would be his reaction, if Bitcoin climbs to new ATH after the next block reward halving (I am not joking, as of now there is a very strong chance of another bull run just like what we had during the second half of 2017).
As someone pointed out above, he probably entered with a huge capital. So he probably did what most institutional traders do. Enter at a desired price point, set a desired take profit, and a stop loss. He probably just hit the stop loss and triggered the sell is all. He might have lost $130M but we don't know what the capital was. Was the loss 1% of his bankroll? 5%? That's acceptable risk in any measure of market trading.
I've lost plenty of money myself trading and gambling but these were all acceptable losses, at acceptable risks.
