Items in the front end like the drag link and tie rod are mounted on ball joints so they do and are supposed to be able to rotate about their long axis. What they should not have is any side-to-side play at where they are mounted.
With the tires on the ground, have a helper turn the steering wheel back & forth (engine can be running) while you watch the front-end components for unwanted side-to-side movement at what they are bolted to. Especially at the track bar's passenger side mount where it bolts to the bracket on the axle.
The two most common causes of DW that are often paired together are imperfectly balanced tires, they must be perfectly balanced, together with a loose passenger-side track bar mount.
Other causes can be worn control arm bushings, improper toe-in, bad ball joints, loose anything. All of the front end must be tight and have no slop in anything. Remember the drag link and tie rod can be rotated a little back & forth by hand, that is normal.
For DW to develop, it must be triggered by something like an out of balance tire or a bump in the road. Then once triggered, a tight front-end will dampen out the shock & momentary oscillations caused by the trigger. A front end with something loose will be unable to dampen out those oscillations which will grow in intensity until DW is fully developed.