I got curious as what happened to the other 4. Wikipedia lists them as extrusion presses being scrapped in the 90's and 2021 in Maryland and Torrence CA. https://en.wikipedia.org/wiki/Heavy_Press_Program

I wonder if they wore out?, something better came along?, or just no demand?

They've been maintained, wear parts such as bearings and seals can be replaced. You can keep well-made machinery running almost indefinitely if you take care of it.