I put “hack” in quotes because at the time the community loudly was proclaiming “code is law” and if you accept that the person accused of hacking didn’t break any “laws” of the DAO…he simply used it according to the code published in the smart contract. The community decided to hard fork, change the rules and censor his transaction.
You could make the same argument that was censorship in bitcoin had a transaction been made that exploited the inflation bug before the fix was pushed out: https://bitcoincore.org/en/2018/09/20/notice/