I am not sure where you are coming from with that comment. Microsoft hasn't broken backwards compatibility on anything that I'm aware of in some time.

.NET Framework to .NET Core transition, Xamarin.Forms to MAUI, XNA, the multiple rewrites on the WinRT platform since Windows 8, Windows 8 to 10 users pace drivers framework, .NET Native, C++/CX, Win2D, WinRT for XBox replaced by WinGDK, .NET Sharepoint Framework via a JavaScript one,

exactly zero of those things break backwards compatibility.

programs written using ANY of those technologies run on Windows 11 unmodified, and they will for Windows 12, too.

backwards compatibility means new OS versions can run programs written for older OS versions.

backwards compatibility promises do not prevent you from coming up with new ways to write programs.

Except when the old way no longer works, the bugs don't get fixed,tooling disappears from Visual Studio.

I am on the Microsoft ecosystem since MS-DOS 3.3.

I still don't think you know what backwards compatibility is. you are saying anything necessary to shut me up and concede and this point, and since you are confused about backwards compatibility, you are not correct.

backwards compatibility is not about keeping all features once supported in visual studio in all future versions. that is forwards compatibility. Microsoft does not do that.

we are talking about backwards compatibility: the ability of new operating systems to run software unmodified which ran on old versions of the same operating system.