Well every source I have found so far has said that aloe vera is a humectant:
Look under the "What you can expect" heading
Look at the end under "External Uses" then under "Cosmetic and Beauty Care"
However I have found that "Aloe Vera gel is only a fair humectant. When tested with two other commonly used humectants, propylene glycol and glycerin, Aloe performs reasonable well. But, when Aloe Vera gel is mixed with either propylene glycol or glycerin, it has a synergistic action as a humectant."
But what makes this even more confusing is that by some definitions, including the Merriam-Webster dictionary, a humectant is simply anything that "promotes retention of moisture" or is "a substance that absorbs or
helps another substance retain moisture."