Why should security be the sole responsibility of the account holder? If my house got broken into I wouldn't expect people to blame me for not storing my wallet in a safe.
Nor would I expect my bank to let someone crack my credit card pin and not alert me something was up.
Madness.
So, if your house will be broken, you will blame doors manufacturers, because the cheapest doors are not secure enough? I feel sorry for people who had their NXTs stolen, but I don't think that it's developers fault.
I think in this case, the developer is partly to blame.
Bitcoin public / private keys have been quite secure for 5 years now.
But the developer of Nxt decides to come up with his own novel strategy that encourages accounts from being hacked. Nxt is likely the only crypto currency where you routinely hear people complain about their individual wallet being hacked. The inside joke is that you can mine Nxt wallets using GPU farms.
Anyway, NEX already has made the necessary code changes to use bitcoin technology rather than the flimsy one used by Nxt. Consider NEX like 'industrial strength Nxt'.