This would need an extremely robust real world identity system. If this was left to governments somehow, then the identity system itself would become the single point of failure and the main way to game the system through corruption. This is already the case in developing countries where deaths are purposely not recorded in order for the relatives to collect pensions and other contributions.

Building such an identity system algorithmically on top of a social network also doesn't seem to make sense because this can be cheated too.

One solution that might work would be to prove that you are a conscious person to a system like ethereum through a "Ghost Key" like in Ghost in the Shell. Assuming that there is a way to "fingerprint" each person's ghost, such as creating a hash of something that doesn't change, that could be like e key to such funds. I highly doubt that there is something constant in the human connectome though.