thought provoking piece, I think a new parallel gross and net settlement network will form with main chain lightning, ecash and hopefully a temporary bridge with fiat through atomic swaps as theorized
with regard to VISA and other card networks its important to note these entities take on enormous risk of consumer charge back protections justifying some costs however in my experience with the interchange fees they are exorbitant to pass onto consumers and represent real need for improvement in the system, lightning and ecash pro probably contain a more elegant and cheaper solution
most global capital flows in trade, FDI, securities settlement, payroll etc still operate on central bank clearing, cross boarder and local paymen systems. We need to reimagine ways to bring these high value (non-consumer) flows into Bitcoin settlement systems
stable coins have had one critical function though at least historically - arbitraging the Bitcoin price between exchanges globally, avoiding SWIFT rails
this concept of "sable balances" is an interesting fait-less way of handling settlement too and could been round about way avoiding the banking cartels