If maintaining critical infrastructure like bridges and tunnels worked like deploying software updates, every few weeks the bridge or tunnel would close itself to traffic in one direction for a while, without warning.
Every now and then when the tunnel reopened, it would feature a loop-the-loop hidden inside the mountain. While it looked the same from outside, it would therefore become completely impassable by large amounts of the traffic that used to rely on it, including ambulances, food supplies, and the CEO's limo.
Every couple of years, your world famous suspension bridge, used as a widely recognised landmark by millions, would be redesigned more like a Roman aqueduct. With traffic driving on the opposite side of the road. And a high speed railway line running right down one of the traffic lanes. With warning signals that are supposed to alert motorists to the danger, but in practice don't because none of the motorists know what the funny symbols mean.
When software engineering is at least on the same planet as civil engineering, and software updates are subject to the same standards of oversight and approval before being deployed, we can talk. Until then, organisations can and will see software as a tool that is there to do a job, and view updates to working software as a high risk that isn't worth taking if it might stop that software from doing its job. It might be inconvenient for the software developers, who naturally would prefer everyone to bend to their will and never to have to maintain anything older than five minutes, but those software developers are going to have to realise at some point that the world doesn't revolve around them.