Hi there,
We apologize for the issue you are facing while trying to use Lightroom Classic after the 8.4.1 update.
Would you mind going to the Preferences for Lightroom Classic, then navigating to the Performance tab and setting the option to Use Graphic Processor to OFF.

Once you have made the changes, please quit and relaunch the Lightroom Classic and check if that helps.
If you are able to see the images after setting the Graphic Processor OFF, then I would recommend installing the latest drivers from the manufacturers website prior to switching the option back ON.
You can also check the below mentioned article for assistance.
https://helpx.adobe.com/in/photoshop/kb/troubleshoot-gpu-graphics-card.html
Regards
Nikunj