I think the list of hacked exchanges is far far longer. Somewhere i have seen a list of 20+ names. And even that was probably not complete.
From all the crypto coins ever been stolen , i believe more then 98% of them were stolen from the exchanges (world wide).
The future is decentralized !
Exchanges including.
And this theft is a good lesson for anyone who cares about his crypto coins.
I´m sure that there are more exchange hacks and eventually some unreported minor ones as well. I just mentioned the biggest incidents to show how bad it can end after all by using a centralized service for cryptos...