Current generation of banking software is expanding on the mainframe:

IBM Z mainframes play a pivotal role in facilitating 87% of global credit card transactions, nearly $8 trillion in annual payments, and 29 billion ATM transactions each year, amounting to nearly $5 billion per day. Rosamilia highlighted the continuous growth in demand for capacity over the past decade, which has seen inventory expand by 3.5 times.

https://thesiliconreview.com/2024/04/ibm-new-mainframe-web-t...