We understand your frustration. Thoracic outlet syndrome (TOS) can be very difficult to evaluate and treat. The treatment should match the underlying cause but it's not always possible to know what the real problem is.
When surgery is indicated the surgeon might take a more conservative approach. Removing part of a rib can't be undone so rib-sparing surgery is often tried first. If the patient doesn't improve, then the second more advanced operation is still possible.
It's thought that the rib pushes up against the bundle of nerves as they leave the neck and go down the arm. In some cases the nerves might naturally dip down toward the first rib. Either way compression is taken off the nerves by removing a section of the bone.