UNIX is not a thing anymore, nobody writes UNIX code. People use various compatibility layer or straight up use kernel abis. And they are all improving over time. So no they are not all stuck in 80s. Even linux kernel devs are willing to add rust code in the mix.

> Windows, where the focus is C++ and .NET,

Microsoft is huge organization they have multiple focuses. You seem to be mixing the kernel/userland layer and making very weird argument against UNIX(that nobody uses).

I am not familiar with COBOL is there any effort to improve COBOL?