@Chned , From your description, I know the Device Configuration profile for pushing WIFI setting is working well. But we see failed error for system account on the device status. We also configure other device configuration profile for Windows Hello for Business which shows successful for System account, If there's any misunderstanding ,please let us know.
Based on my experience, the result depends on the setting. For the WIFI setting, it may need user login to configure the WIFI profile using the user account. When the policy is deployed to the device which is not login with any user account. The system account will be used to configure the profile which will cause it failed. But when we login with user, if we can see successful result for this user account under device status. It means the policy is deployed successfully. We can safely ignore this error with system account. For other setting like Windows Hello for Business, it can be configured with system account, so it shows successful. That is to say, it depends on the setting itself which you configured.
Hope it can help. If there's anything unclear, feel free to let us know.
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