There is some logic to running older stuff, a lot of it is a closed system and it’s harder for threats to target it. Banks are a big one that still run a ton of our financial infrastructure on COBOL.

Hospitals also run on a ton of abandon ware, same with machine shops. Ultrasound machines that are still running 95 because for the hospital to upgrade to windows 7 or 10 is millions for a few machines. So you just airgap the systems for security.