Roast me if you want, but out of all the cars I've had over all the decades. I have never changed PS fluid. The last issue I've had with a PS steering pump was a blown hose in a '67 Cougar (pump was fine). Never had a pump fail yet and I keep cars 10 years or more. Current ride is going on 18.
They are "life time" fluids. So for the life of the tranny you don't needs to change fluid.
The life of the tranny might be short because you did not change fluid, but the fluid will last the life time of the tranny. (loser)