In a rather shocking move, Microsoft announced it has ported the user mode D3D12 runtime to Windows 7. This work was done at the request of Blizzard, which wanted to bring the performance gains of the DirectX 12 version of World of Warcraft to gamers with older versions of Windows.
Despite Windows 7's retirement on January 14, 2020, Microsoft still put in the work to enable this, and is even working with a few other game developers to port their D3D12 games to Windows 7. It's bizarre to see the addition of such a big feature to Windows 7, especially as mainstream support for that operating system ended on January 13, 2015.
Of course, Microsoft still recommends gamers to use Windows 10, claiming the latter offers the best DirectX 12 performance:
Today, with game patch 8.1.5 for World of Warcraft: Battle for Azeroth, Blizzard becomes the first game developer to use DirectX 12 for Windows 7! Now, Windows 7 WoW gamers can run the game using DirectX 12 and enjoy a framerate boost, though the best DirectX 12 performance will always be on Windows 10, since Windows 10 contains a number of OS optimizations designed to make DirectX 12 run even faster.
We’d like to thank the development community for their feedback. We’re so excited that we have been able to partner with our friends in the game development community to bring the benefits of DirectX 12 to all their customers. Please keep the feedback coming!