As you said, is somewhat nonsensical because it suggests that someone looks old and young at the same time.(*) I feel like it at least needs some qualifications, like "his _physical features_ may look old when taken individually but his _overall impression_ is not that of a typical old man". (This is just a made up example, other qualifications are possible.) Perhaps the writer might assume the reader knows the unsaid qualifications so they don't see the need to clarify, though.
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