It's not the only the correctness of the debits and credits that is possible, but also determining their nature. Of course these implementations would have to be molded to fit for each use case. The technology is nascent.
The blockchain's (current) prime use case: triple entry accounting. In double entry accounting, a ledger only contains debits and credits. With the blockchain, the blockchain's attestation of the validity of the debit and credits is the third entry. This removes the need to trust whether the credits and debits were correct in the first place. Were financial systems to be based on blockchain design, an Enron situation would not be able to occur. It might even prevent the likes of Madoff. This technology is only getting started. While there is hype, this hype is necessary for the market to test out many ideas and applications, until those that make sense remain standing.
An incorruptible ledger resistant to the control of any individual, corporation, or state. Bitcoin may fail in its implementation of this goal. The future is still to be determined.
Bitcoin's underlying technology creates the possibility of decentralized governance, starting with currency, which is the connecting link between actors in societies based on economy.
Why such a future might be beneficial to mankind is that banking and finance being controlled by a few has led to errors with systemic consequences.
See the 2008 financial crisis and hyperinflation in Venezuela and Zimbabwe. See the seizure of funds by governments from individuals in Greek and Cyprus, scenarios where many of the affected did not write their own doom (others wrote it for them).
You are throwing away the possibility that there is an intrinsic value in Bitcoin, more related to socio-economic-political concerns, than survival. There is not only one domain in life.