Most people of any significant wealth would have made the delegation long ago to private client banking where a team of people overlook all aspects of the accounts. So yes, you are a fool not to if you have the level of wealth proportional to having it beaten out of you in your geopolitical region.
A custodial service is a bank that operates on a different network and is not FDIC insured (which only covers $250k). It could be insured privately. The interest on an FDIC deposit account is well below true inflation of fiat currencies.
So, you want to delegate your ability to spend your money to other people.
Why not just go to a bank? It can do that for you, plus pay you interest.