Microsoft has removed a compatibility hold that prevents users from upgrading to Windows 10 1903 and Windows 1909 if they are using older Qualcomm Wi-Fi drivers. Microsoft first applied this update block on May 21, 2019, after users were reporting that they were experiencing sporadic loss of connectivity after upgrading to the latest version of Windows 10. Users would also be shown a message if they attempted to use the Windows 10 Upgrade Assistant or the Media Creation Tool explaining that they need to install a new version of the Qualcomm wifi drive in order to continue.
Source: https://www.bleepingcomputer.com/news/microsoft/microsoft-fixes-windows-10-qualcomm-wi-fi-driver-update-block/