This is an issue exclusive to Windows 10 2004.
Did not find much on this topic besides a reddit post that was hard to find. So posting here to give a heads up. Hopefully will get fixed soon.
-latest updates to topic-*
*Related known issue; due to the blank icon if you update chipset drivers, monitor drivers or graphics card drivers this will cause your windows icon cache to refresh causing windows to no longer detect the installation of pso2.
*I have contacted microsoft, xbox live and sega roughly about five times trying to troubleshoot issues with pso2. None of them are taking responsibility as of yet for issues related to blank icons and keeping Windows 10 2004 from no longer detecting the installation of pso2.
*(TLDR-Some of these are advanced troubleshooting techniques and I do not recommend you attempt them unless you know what you are doing, but as stated here they will not resolve the issue at present time.) Troubleshooting i have attempted to resolve the issue includes; Clean Install of Windows 10 2004, DISM scan/restorehealth, SFC scan, Windows Store Apps TroubleShooter, wsreset, repair or reset under setting>apps>PSO2, changing icon of the .exe file using a 3rd party resource tool, going into Regedit to point to the icon path file directly, clearing windows icon cache and rebuilding it.