SWIFT? Hold my beer. SWIFT did not launch anything substantial since its startup days in early 70-ies.

Moreover, their core tech did not evolve that far from that era, and the 70-ies tech bros are still there through their progeniture.

Here's an anecdote: The first messaging system built by SWIFT was text-based, somewhat similar to ASN.1.

The next one used XML, as it was the fad of the day. Unfortunately, neither SWIFT nor the banks could handle 2-3 orders of magnitude increase in payload size in their ancient systems. Yes, as engineers, you would think compressing XML would solve the problem and you would by right. Moreover, XML Infoset already existed, and it defined compression as a function of the XML Schema, so it was somewhat more deterministic even though not more efficient than LZMA.

But the suits decided differently. At one of the SIBOS conferences they abbreviate XML tags, and did it literally on paper and without thinking about back-and-forth translation, dupes, etc.

And this is how we landed with ISO20022 abberviations that we all know and love: Ccy for Currency, Pmt for Payment, Dt for Date, etc.

Harder to audit when every payload needs to be decompressed to be inspected