Running simple bank-transfers uses trivial amounts of power. They could do this stuff for like 30 years, whereas crypto still is nowhere near the transaction volume of banking and already takes the amount of power of a small or medium-sized country.
The blockchain might not have been hacked, but exchanges have. Or gone bankrupt, like FTX.
In the USA, and probably most other countries, the government provides insurance for bank deposits (e.g. FDIC). So, even if the bank gets robbed, you can still get your money back.
That doesn't apply to most investments, however.