I even believe that the Tractor Beam effects initially only had the move component, and then FFG added the -Agility one because it felt so lackluster. Then they reduced the price to the minimum.
Sure, it sounds dangerous. Sure it sounds disruptive. But even when it disturbs one of the core aspects of the game (positioning), it doesn't do any direct damage (that is how games are won anyway), and the victim still has its whole dial available next round. You cannot even change the current bearing of the victim, only shift it a bit. For 2 points more, the Ion Cannon deals damage and removes the dial for one entire round. And how many use Ion Cannons today? And the Ion Cannon even affects Large and Huge ships in some way, while the Tractor Beam does little to Large Ships, and nothing to Decimators, VCX-100s, or Huge ships.
Also, most of the ships able to equip it are currently in need of a little boost (except the Aggressor) due to recent changes in the meta (or inherent shortcomings of the ships themselves), or they are so expensive that your realistically will face one at the same time, or they are easily outflown, or several of these conditions at the same time.
I expect it to be popular for a couple of months, for the novelty, then it will fade and be seen as often as the Ion Cannon, or slightly more due to it's cheap price, or TIE/D Defenders or "Mist Hunter" G-1As. Still, I think TIE/Ds will sport a Ion Cannon whenever possible, and only the Tractor Beam when the Ion Cannon doesn't fit.