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And therein lies the key. While in books, we may have pieces that are written for purposes of exploring an intellectual curiosity, for economic reasons modern TV and movies must also satisfy the viewer's need for escapism. Real technology does not provide escape from the real world, because it is too real. We recognize it too easily, and it does not make us think much. While you can have a show with such technology in it, it will not be known for its tech. It will instead be known for that which provides the escape - basically, it will seem to the viewer like it is in another genre. Which is a perfectly acceptable thing to do, but it won't look like science fiction. It'll look like a mystery, or a thriller, or a drama, or what have you, with slightly advanced technology.
Person of Interest shows this concept quite well. The baseline tech includes effective AI with almost unlimited surveillance capability, pattern detection and recoginition. But, in effect, it is a basic "people outisde the law out to help others" show.