It's possible more than one system could replace SWIFT, but why would it be Stellar/Lumens who are still in the gate with their fork when Ripple/XRP seem to be already round the first bend with seemingly very large momentum in terms of interest, trials and actual production use by financial institutions?
How is Stellar still "in the gate," more than two years after deploying their decentralized Byzantine agreement algorithm?
Ripple has only just now, in 2018, published their decentralized consensus algorithm (Cobalt), which as far as I know is not even in production use yet, and doesn't provide optimal safety. (In settings where Cobalt is guaranteed Safe, SCP would be too, but not vice versa.) Their production network still uses a protocol that, by Ripple's own analysis (https://arxiv.org/pdf/1802.07242), fails to guarantee safety without >90% agreement on the UNL.
Yes, but perhaps your framework for approaching this is a little too old school?
When SWIFT was devised, the idea of having a singular system for resolving these transactions not only made sense but was (probably?) technically necessary. I think given where we are today, multiple competing protocols, each with their own advantages, may be viable.
Lastly, for finance, consumer choice is valuable: I like being able to Venmo my friends, autodeposit my landlord, slow mail my bills, and Apple Pay my retail purchases. I don’t send money overseas but I could imagine a similar bifurcation of solutions in this space, all with their own advantages.
