. Either the coins will be passed to your trusted person if the account is inactive for a specific amount of time or your family can submit a death certificate. This sounds to me a fool proof function. Could there be downsides to this function?
See
here.
The first downside about the whole idea on this is that we are dealing with a centralized exchange here. And anything could go south, either through an act of the exchange or through external attacks and users could lose their funds.
Best any bitcoin holder could do to themselves and posterity is to have their coins stored in self custody, by using a noncustodial wallet. And good enough, there are now different available recommendable ways users can use to timelock and keep their coins safe for the future or pass it to next of kin instead of using an exchange.