From my point of view, there were two big problems with WinRT when Microsoft started pushing it, and for a long time afterward: the biggest part of the API, the

From my point of view, there were two big problems with WinRT when Microsoft started pushing it, and for a long time afterward: the biggest part of the API, the XAML UI framework, couldn't be adopted in an unsandboxed Win32 app until 2019, and there was no way to use that UI framework on Windows 7 (e.g. through an OS update or a backported redistributable runtime). So as a third-party developer looking at this in the mid-2010s (before I went to Microsoft), I could develop an app that ran on Windows 7, an app that used the native framework of Windows 8+, or both, but the same app couldn't do both. I chose to keep targeting Windows 7, and not use the newer UI framework.