Hi there,
The processor are selected by various parameters and the important one is DCH Design Principles.
https://learn.microsoft.com/en-us/windows-hardware/drivers/develop/dch-principles-best-practices
You can check out the other reasons for the processor selection from here
https://blogs.windows.com/windows-insider/2021/08/27/update-on-windows-11-minimum-system-requirements-and-the-pc-health-check-app/
Some of the 7th generation processor and all 8th generation Intel processor and their equivalent AMD are supported for Windows 11. It seems your Ryzen 5 2400G is not in the list and it might not support the Windows 11.
Hopefully it might be added in future based upon testing by Microsoft.
Windows 11 supported AMD processors
https://learn.microsoft.com/en-us/windows-hardware/design/minimum/supported/windows-11-supported-amd-processors
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