Banks could save themselves CPU, RAM, bandwidth, and liability by implementing read-only API tokens and methods that need only return JSON - instead of HTML or worse, monthly PDF tables for a fee - possibly similar to the Plaid API: https://plaid.com/docs/api/
There is competition in consumer/retail banking, but still the only way to do e.g. budget and fraud analysis with third party apps is to give away all authentication factors: u/p/sqa; and TBH that's unacceptable.
Traditional and distributed ledger service providers might also consider W3C ILP: Interledger Protocol (in starting their move to quantum-resistant ledgers by 2022 in order to have a 5 year refresh cycle before QC is a real risk by 2027, optimistically, for science) when reviewing the entropy of username+password_hash+security_question_answer strings in comparison to the entropy of cryptoasset account public key hash strings: https://interledger.org/developer-tools/get-started/overview...
> Sender – Initiates a value transfer.
> Router (Connector) – Applies currency exchange and forwards packets of value. This is an intermediary node between the sender and the receiver. {MSB: KYC, AML, 10k reporting requirement, etc}
> Receiver – Receives the value
Multifactor authentication: Something you have, something you know, something you are
Multisig: n-of-m keys required to approve a transaction
Edit: from "Fed announces details of new interbank service to support instant payments" https://news.ycombinator.com/item?id=24109576 :
> For purposes of Interledger, we call all settlement systems ledgers. These can include banks, blockchains, peer-to-peer payment schemes, automated clearing house (ACH), mobile money institutions, central-bank operated real-time gross settlement (RTGS) systems, and even more. […]
> You can envision the Interledger as a graph where the points are individual nodes and the edges are accounts between two parties. Parties with only one account can send or receive through the party on the other side of that account. Parties with two or more accounts are connectors, who can facilitate payments to or from anyone they're connected to.
> Connectors [AKA routers] provide a service of forwarding packets and relaying money, and they take on some risk when they do so. In exchange, connectors can charge fees and derive a profit from these services. In the open network of the Interledger, connectors are expected to compete among one another to offer the best balance of speed, reliability, coverage, and cost.
W3C ILP: Interledger Protocol > Peering, Clearing and Settling: https://interledger.org/rfcs/0032-peering-clearing-settlemen...