The distruss to software is not against all software. Blockchains are usually advertised as trustless, so the argument against that has to be made as you have to trust the devs. The trustless argument is weak on other fronts also, but this is one side of the issue.

Banks and firms that uses their services are audited thoug. It is not blind trust. And regadress the tech used there would sitll be audits.

You dont need 51% attack to corrupt a ledger. Just enter incorrect info and the ledger is wrong. Not a damn thing a blockchain can do about that. Same issue is with any trustless system where you have to trust someone to input the correct info/do the agreed thing/ship the ordered physical item.