Confusing requirements for key attestations

The text here looks confusing:

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<img width="772" height="238" alt="Image" src="https://github.com/user-attachments/assets/38b05dd9-c60e-4a7a-8b53-7e65b6ddac15" />

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I think the 'MUST' for the proof types is not intended to be a MUST given the 'SHOULD' in the following section.