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Arnab Biswas thank you for answering this during today's live episode.
One way Microsoft could quickly and immediately address this would be to slighly alter the Pre-install script exit code check.
Currently according to https://learn.microsoft.com/en-us/mem/intune/apps/macos-unmanaged-pkg documentation, "Pre-install script: Provide a script that runs before the app is installed. Only when the preinstall script returns zero (indicating success), the app proceeds to install. If the preinstall script returns a non-zero code (indicating failure), the app doesn't install and reports its installation status as "failed". The preinstall script runs again for failed installations at the next device check-in (sync)."
Microsoft could enhance this to provide a way for the admin to indicate a package is already installed by offering a custom exit code the pre-install script can return (eg exit code 2 for "package already installed"), so the reports show the installation status as "success".