A 1959 programming language, COBOL, is powering global finance and government systems. As experienced programmers retire, companies face a talent crisis. This has created a lucrative opportunity for new developers learning this older skill. Banks and agencies are paying top salaries to maintain these vital systems. AI is also being explored to help manage COBOL code.
Also, all hardware components are hot-swappable.
They have a lot of built in redundancy.