Microsoft explains why it must retain the old interface and Windows 11 has not yet escaped that

While Microsoft pushes to refresh the Windows 11 interface, an article from 2003 by Microsoft engineer Raymond Chen partly explains why many old interface elements still exist today.

Why hasn't Microsoft been able to completely remove Win32 from Windows 11?

At that time, Microsoft did not immediately remove the old interface but provided the option for users to return to the familiar way of operating during the adaptation period. For example, when Windows 3.1 introduced the new Alt+Tab window switching mechanism, the company still allowed users to restore the old behavior of Windows 3.0 through Control Panel.

The old Alt+Tab mechanism is based on the stacking order of windows, similar to Alt+Esc. Meanwhile, the new method is called "fast task switching" by Microsoft. The company even provides a SPI_SETFASTTASKSWITCH setting so the software can revert to the previous way of switching windows if needed. The reason behind is that large businesses do not want the software interface to change too quickly. According to Chen, a company with 10,000 employees may have to spend millions of dollars to retrain personnel if the interface changes, even though that change may bring a better experience.

The fact that Windows must support a large hardware ecosystem, especially in corporate environments, makes it difficult for Microsoft to quickly remove old components like Apple does with macOS. Just one careless change can affect the equipment, software or operating processes that the business depends on. Besides, Windows is also influenced by the history of software development with many successive interface frameworks, from Win32, MFC, .NET, XAML, UWP to WinUI 3. The constant change of platforms causes many Windows applications to now switch to using WebView2 or web technology, instead of a complete native interface.

Windows Latest says Microsoft is starting to change this approach in 2026. Some long-standing components are being rewritten with WinUI 3 instead of just replacing the outer interface layer. File Explorer's new Properties dialog box, for example, replaces a Windows 95-era component.

The new Run dialog box has also been optimized by Microsoft. Telemetry data shared by the company shows that the new version loads in 94 ms, faster than the old dialog box's 103 ms. This is a detail that shows that old code does not always survive because of better performance, but often because rewriting it while still ensuring compatibility is a complicated task.

Microsoft is also gradually migrating the Start menu's common interface infrastructure to WinUI to improve interaction latency. Part of the Windows 11 Start menu was previously developed with React Native to support faster testing and deployment, but the company now prioritizes performance, platform stability, and bug fixes before fully replacing it. It can be said that Windows 11 still carries many traces of previous generations of Windows, but Microsoft is gradually switching from "overlaying" a new interface onto the old platform to rewriting important components. This process will not be fast, because Windows still has to maintain compatibility with the huge hardware and software ecosystem that has existed for decades.