There's a serious advantage to becoming fluent by moving to a country that speaks that language fluently. Try becoming fluent in Japanese in Nigeria for "Japanese hard mode"
It's "legacy" because it's essentially tied to Windows. Yes, technically it works on Linux, and no doubt that was an amazing feat, but no serious company is running MSSQL on Linux when all the documentation, all the best practices are all based on running that on Windows.
You don't have to make a complete alternative. You can add calls to ATK (accessibility toolkit) on Linux/Unix platforms. I'm not sure what needs to be done on Win32 platforms though.
The best example I can think of is the Win32 controls UI (user32/Create window/RegisterClass) in C. You likely can't read the source code for this but you can see how Wine did it or Wine alternatives (like NetBSD's PEACE runtime, now abandoned).
Actually the only toolkit that I know that sort of copied this style is Nakst's Luigi toolkit (also in C).
Neither really used inheritance and use composition with "message passing" sent to different controls.
Vibe coding in the 90s was probably like learning C and pointers for the first time and then deciphering strange errors when you couldn't figure out how scanf worked, so you added asterisks and ampersands to the code until it compiled.