Hexing is unfortunately all over the place in the original fiction. As mentioned in previous threads, early Dresden books made a big deal out of the ramifications of having an agitated Wizard near your tech. Later books, however, highlight the newer Warden recruits regularly running around with technologically advanced firearms. One can make a case that they are younger and therefore less likely to hex things closer to tech from their own adolescence, and in some part this is covered in the Hexing table.
But between the fiction and the RPG, it remains pretty solidly as a GM Compel. In the fiction, it comes up when dramatically poignant, when a tech shortcut would make things too easy. In the RPG: same thing, and it serves as a potential vector for Fate Points to get back to the player, though whether you consider them "free" Fate Points, or a Compel of the spellcaster's High Concept is a matter of semantics.