It's always you who's responsible for this. For instance, I store all my funds in my Freewallet app and I have 2fa and PIN set, so it's almost impossible to steal my coins.
With wallets that may be true, but I guess the OP is talking about accounts in cryptocurrency exchanges. If someone hacks the exchange accounts, then you can't just blame the users. The exchanges should also bear a part of the blame. Here, security precautions such as 2FA and email verification are the responsibility of the exchanges. I own accounts in several cryptocurrency exchanges, and till now none of them have got hacked. But some of my friends were victims of such hacks. And they never got any sort of compensation from the exchanges.