MFA enrollment, key rotation, and key retirement are distinct operations. An enrolled device protects an interactive authentication path, while an access key remains a separate credential. This local account models the enrollment flag and key status; the sample codes and key material are fictional and can't authenticate to AWS.
A safe rotation creates the replacement before retiring the old key. In a real account, update and verify every consumer before disabling the old credential, then monitor for missed dependencies before deletion. Here, the exercise explicitly tells you which consumer migration has already been verified. Deactivating the replacement instead of the old key defeats the rotation. Do not remove an MFA device casually either: the retirement task represents an authorized device replacement with a separate trusted recovery path.