The notions of security that are relevant should also include stability of the banking & payments system in the GT context. What alterations are needed to protect both financial commitments & assets of payers & payees?
In a parallel channel, I gave the opinion that providing broad, distributed basis of corporate control & financing in the form of confederations of distributed LLC & LLP can be automated for managability & convenience while offering greater robustness to powerful spy crime assaults. The basic story with banking & payments may be similar. If any payer or account is individually vulnerable to big diabolical plot, then automating distributed support over a lot of nominally independent pots makes it harder for spook to manage their sinister aims & gains.