If it's your job to do what is requested from you, then you do it. It's not like having brittle unmaintainable code is morally wrong. It's not engineers responsibility to judge use case of the customer paying for the bridge.
Actually yes, yes it is! I am a civil engineer and there's a standard of ethics and personal responsibility among engineers that is very, very high. When we graduate, most engineers participate in a ring ceremony. They get a funny, angled ring on their right pinky. It was originally made from the metal from a bridge that fell down and killed people. It was meant to be a daily reminder, worn on the drafting hand, that every single drawing you signed carried the weight of public trust of their lives. Even pedestrian bridges get built with vehicle load standards, because you can't just assume that it will only be used by pedestrians.
Civil engineering is a licensure, and no matter what liability structure you use, when you stamp a drawing, you carry PERSONAL liability for anything that might happen if that design fails. Even small violations of ethics or operating outside your scope of knowledge are dealt with very aggressively by the licensing board.
In school, if we misplaced a decimal or got a calculation wrong or failed to adhere to a very specific standard, it was automatic failure because if you do that in real life, people die.
And that is because no one can just go to a 6-month bootcamp and call themselves a Civil engineer. And even if they did, no one would hire them or the employer would go to jail.
If we want Software Engineering to be as rigorous as other Engineering disciplines, we need to erect similar barriers to become a Software Engineer.
It's strange too, you hear in other threads about how high the demand is for software engineers, how high their salaries are, how much negotiating power they have with their companies, but when it comes to the actual product content, suddenly they have no power at all and it's just Yes boss, whatever you say, boss. How is this true?
Anyway for most systems deployed the customer usually wants to maintain a business using it. If the system constantly falls over, cant be readily changed etc etc that is going to cost the customers business compared to its competitors.
Add that a lot of developers work for the same company as the customer and that is just as much the developers responsibility.
99.999% of bridges built would be expected to hold up 10 years later and require minimal maintenance. I'd wager all bridges even temporary army ones would be expected to not unforeseeably fail. See the Morandi Bridge tragedy.