I can tell you something you can’t Google in 2 seconds: have a close friend who’s also a programmer that worked on SWIFT: the transactions are conducted through XML files on FTP(!) drops.

What the heck. I can’t wrap my head on how that would work. Can you elaborate?

Yep, and actually I worked on the US Federal Financial Aid system and the transactions between the DOE and schools work the same way (called SAIG Mailbox)

Look up ISO 20022 and “store and forward”

There isn't anything really in this "explanation" that cannot be googled within seconds much less that would require him to be an expert. For me it explains nothing. I don't know, maybe it is a little enlightening for a person that never heard of SWIFT before, that didn't know it's "something related to international payments" and now he does. But I'm not sure this qualifies as an explanation.

He's an "investor/entrepreneur" FWIW.

To read, you can always use ThreadReader. Just pop the Tweet's URL in there:

https://threadreaderapp.com/thread/1496861068945154056.html