Microsoft has announced that Windows Subsystem for Linux 2 (WSL2) will be kept updated via Windows Update. WSL2 will use a real Microsoft-compiled Linux kernel based on the stable 4.19 version release of Linux at Kernel.org. Windows 10 users will need to manually download and install the latest WSL 2 kernel using these instructions. In a future update to Windows 10 2004, though, Microsoft plans on distributing new WSL. 2 kernels via Windows. Update.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-2004-to-upgrade-wsl2-linux-kernels-via-windows-update/