Yes, it is - when there are a bunch of "this is a picture of John" posts mostly by identifiably pro-1st/2nd/4th/10th Amendment[1] types, facilitated by face recognition software confirming it's the same John, whereby data mining can determine that there is an un-tracked person named John who is most likely a pro-1st/2nd/4th/10th Amendment type and, because of his pointed absence from social media, likely rather hardcore about it and worth tracking with particular interest.

Tom Brown (famous tracker) tells a story of his tutor telling him "go to the grandfather tree." He scoured the woods for the curious plant, and found nothing. Standing in a clearing wondering what was meant, he realized that the space he was standing in - an unusually empty space in an otherwise dense forest - must have been created by a very large and very old tree that had subsequently fallen and rotted away, leaving a space other trees had been unable to grow in. Moral: an apparent absence can, coupled with identifiable effects, be indicative of something very interesting; to wit if there's a lot of pictures of someone but nothing from that someone he's probably hiding something.

[1] - terms for various passionately-defended civil rights here