According to Alaska Airlines employees determine subjectively what they consider appropriate given their own biases, prejudices, and beliefs. And I can actually accept that because Alaska underscores that “bare feet are never acceptable” and no statement has ever been more true in the history of aviation.
Alaska finally confirms “Alaska does not have a dress code policy that would prohibit this guest’s attire.” So they agree with me – nothing wrong with how this passenger was dressed, which means their non-policy policy is to blame.