What may be perceived as a flaw, may not be so if you go into in depth analysis.
It all comes down to an obvious choice - IYHO which system is preferable - one controlled by any sort of central authority or the one controlled by people themselves.
Tho sole purpose to which governments owe its existence is exercising overreaching authority over individuals in all possible aspects of life among which are even such private things as property and ownership. Governing elites define the rules and decides whether you own something or not collecting their share in the meantime through vehicle known as "tax collection".
On the other hand taking into consideration all possible mistakes that you can make, you and only you control your private key and choose with whom you wish to share it and who should potentially inherit it.
If you do not trust yourself more than you trust existing system you may choose to still consider it as a flaw.

If, and say if since all existing smart contract platforms are centrally controlled and thus vulnerable to potential government meddling in the future, we are to ever have truly decentralized smart contract currency in the future, then any person`s will can be included as an inherent condition of accessing those funds.