Hi @crib bar
Thank you for posting your query on Microsoft Q&A!
Any policies in report-only mode will not impact users, this mode is to determine the impact of a Conditional Access policy, you can review the sign-in logs and your "Usage & Insights" reports to see what the effect of the policy would have if enabled. - https://learn.microsoft.com/en-us/entra/identity/conditional-access/concept-conditional-access-report-only
The Microsoft managed Conditional Access policies are default policies configured and if not explicitly disabled by an admin will be enabled automatically, they are designed to secure your environment if you have not already setup MFA etc.. we have details on those here - https://learn.microsoft.com/en-us/entra/identity/conditional-access/managed-policies
Let me know if you have any further queries and I would be happy to help.
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