Wiki --> A truss bridge is a bridge whose load-bearing superstructure is composed of a truss, a structure of connected elements usually forming triangular units. The connected elements (typically straight) may be stressed from tension, compression, or sometimes both in response to dynamic loads. Truss bridges are one of the oldest types of modern bridges. A truss bridge is economical to construct because it uses materials efficiently.
As long as the concrete is in compression (which can be accomplished via pretensioning), the material can be used successfully in truss bridges.
There was a good FR article last month about the first railroad bridge to cross the Mississippi in 1856. See Bridging the Mississippi: The Railroads and Steamboats Clash at the Rock Island Bridge.
My dad is a civil engineer for 40+ years and had a few of his pretension concrete structures fail over the years.
The designers will always blame loading that wasn’t part of the design requirements, like twisting or “shock loads” during construction...because that never happens, you know.
The support cables don’t appear cosmetic. It is my guess that whoever told them to pull the supports out will be held criminally liable, unless it is a minority or a woman.