-If you have money in bank or invested in stock or somewhere else regulated by government and you dies, bank/stock exchange will contact the nominee when the account goes inactive. but if a person who hold crypto dies, nobody will know about this so the money is lost forever. if the person decides to share the crypto details with someone then its not really a "secured" currency.
-If someone stole money from your bank/stock/credit card account, it can be tracked where the money went and can be recovered by filing complaint with your bank or authorities. but if somone steal your crypto there is no way to get the crypto back.
So how is this a currency of future, did anyone asked these question before?
Well, you are talking about the security from a different perspective. It's not really the security of transaction you are mentioning here. It's the security of passing the ownership only.
Yes, bitcoin transactions are not reversible unlike banking transactions. It is because bitcoin is not controlled by a central authority. So if you have sent out a transaction mistakenly, there is no way to get it back unless the person refunds that through a separate transaction.
The kind of security you are mentioning, is already available in the current banking / legal system. Bitcoin can't be compared to them because it is quite different structurally. If you want to pass your bitcoin holding to your next generation, simply create a will with your private key and keep it under safe custody with a process map to redeem the money. Probably that will help!