@Mark Spencer Okwera, Thanks for posting in Q&A.
From your description, I know you want to categorize devices automatically into groups basing on how they were enrolled onto Intune.
Based on my research, device categories allow you to easily manage and group devices in Microsoft Intune and it will automatically add all devices that fall within that category to the corresponding device group in Intune. To enable categories in your tenant, you must create a category in the Microsoft Intune admin center and set up dynamic Microsoft Entra security groups.
Please note that you must be a Global Administrator or Intune Administrator to do this.
Here is a link about how to categorize devices into groups.
https://learn.microsoft.com/en-us/mem/intune/enrollment/device-group-mapping
Please try above information and if there is any update, feel free to let me know.
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