Read this for OS/2
[https://www.karlstechnology.com/blog/history-of-ntfs/
https://www.abortretry.fail/p/the-history-of-os2]
And this for Windows NT:
[https://www.abortretry.fail/p/the-history-of-windows-nt-31]
"In NT, APIs are implemented as subsystems on top of a native API that isn’t publicly documented. Because of this, Microsoft can have compatibility with many different systems (as the modern Windows Subsystem for Linux shows), and Microsoft can make major changes to the NT microkernel and NT executive without disturbing userland. A program written for NT in 1993 can run unmodified on Windows 11 in 2023 as the entire API and userland haven’t changed while everything underneath most certainly has. "
This is how Microsoft ended ruling the Computer market because it keeps compatibility going on way longer that anyone else.
And that's also why Windows is a buggy mess that causes problems with each "update".
I love Linux but I hate when I have to upgrade a distro or install a different one and an App no longer works so I have to resign myself to use a different App.
And if you need to use some kind of emulator or VM to run something? Most of the time you can have that emulator or VM on Microsoft Windows and for the other times? That's why they implemented that Linux Subsystem.
What? Is Mac only you say? There is probably a clone of that Aop for Windows!
There isn't? Oh well, I guess you are a Mac user then.