As you say that these apps are no longer compatible with macOS Big Sur, why don't you delete them from your Mac? Blocking the error messages only cures the symptoms, not the disease.
Usually, if any app is no longer compatible(usually 32-bit apps) with macOS Big Sur, there will be a line crossing it out in the Application folder in Finder. To remove those incompatible apps, you can drag them to the Trash. However, this action won't completely uninstall the apps from your Mac. Their associated files are still on your Mac.
If you don't want to see the error messages of these apps and other cache files, you can either find them one by one in the Library folder in your home folder or use a professional app uninstalling tool to help you.
You can use iBoysoft MagicMenu. This right-click enhancer contains an app uninstallation feature that can help you right-click to delete the unwanted app and all its associated files.
Here's how:
- Download, install, and open iBoysoft MagicMenu on your Mac.
- Select Extension on the app's main interface and find the Uninstall App feature. Then, click the download button next to it to add it to your right-click menu.
- Right-click the unwanted app in the Applications folder in Finder and then select Uninstall from the context menu. Then, click Uninstall on the confirmation window.
