No new versions of the low-cost Raspberry Pi computer have been officially supported by Windows 10 IoT Core since 2016. The low-cost Raspberry Pi computer has been closely tied to Windows 10 IoT Core since the OS was revealed alongside the Pi 2 in 2015. But in the intervening years the situation has changed, with the last Raspberry Pi that Windows 10 IoT Core officially supported being the Raspberry Pi released back in early 2016.
Link: Windows 10 IoT Core on the Raspberry Pi 4: Will Microsoft support the $35 computer? via www.techrepublic.com