FAIL!
That's
factory.....believe it or not.
It's only on the driver's side and it was one of two parts that were added to prevent loss of steering if the spring bolts ever broke. That cage is on the the front hanger, and there was a small "dorsal fin" looking part that went behind the rear spring eye near the shackle. I forget when the cutover happened, but some of the earliest 1st Gens don't have them. Most of the later models do (unless they were already cut off)
I had to remove the rear one when I added soft springs... they flexed a lot more than stock and would hit it. Then, only the passenger side spring would continue to compress under braking, etc. Made for some VERY interesting handling behavior.
There's really no reason to cut it off, unless it bothers you or if it is somehow in the way of a custom, double-wrapped spring eye.