@James Chan_110, Thansk for posting in Q&A.
For Android device administrator (DA), there is a setting for Samsung Knox only device to block Google backup via Intune.
However, For Android (AOSP) and Android Enterprise, there is no built-in feature to block Google backup via Intune. If you want Intune to implement this feature for Android (AOSP) and Android Enterprise, you can submit your feedback to Intune.
https://feedbackportal.microsoft.com/feedback/forum/ef1d6d38-fd1b-ec11-b6e7-0022481f8472
Thanks for your kind understanding.
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