Hello CyberWorrior,
Thank you for posting in Microsoft Community forum.
I am sorry, we also don't have documentation or information about service hardening guidance on Windows Server 2022/Windows 10 21H2.
And after my research, I only find a similar thread about 2019.
Here is a similar thread about disabling system services on Windows server 2019.
Guidance on disabling system services on windows server 2019 - Microsoft Community Hub
Another guidance on disabling system services on Windows IoT Enterprise
Guidance on disabling system services on Windows IoT Enterprise | Microsoft Learn
If you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou