Hi @Kelvin Rodriguez Thanks for posting in our Q&A.
For our questions, I have done some research.
Q1: The user cannot uninstall Defender on macOS
A1: Currently Intune can't prevent users from uninstalling macOS apps, it's by design.
Q2: If the user uninstalls Defender then the macOS is in non-compliance.
A2: The answer is not possible now. we can restrict apps, if they exist in the device, it will be marked non-compliant. But this is different from what you looking for.
https://learn.microsoft.com/en-us/mem/intune/protect/compliance-policy-create-mac-os
Q3: If the user uninstalls Defender then Intune can install it again.
A3: Push the Defender as Lob apps and set the assignment type as Required. Intune will automatically reinstall, update, or remove a required app within 24 hours. Please refer to:
https://learn.microsoft.com/en-us/mem/intune/apps/apps-add#installing-updating-or-removing-required-apps
We recommend to use Intune User Voice to create or look for existing topic.
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