[2021] Launcher Missing Background?

Have you tried deleting the LauncherAssets folder and starting the launcher? It should then redownload those files.

Best to try a complete clean install of the launcher then, by following the steps here:

https://steamcommunity.com/app/255710/discussions/0/1742265315844206043/

If that doesn't work, you will need to contact Paradox Support.