The thing that makes software different is scale due to low reproduction costs. You can easily envision the costs of adding new labor, for example, in building a car and directly map those expenses to increased production quantity. In that case scale of labor to scale of product is not exactly 1 to 1, but it’s close. In software that 1 to 1 scaling does not exist.
Perhaps the big difference is that few people working a car assembly line are engineers. Most of the labor is produced by manual labor and robots. In software the actual engineering is equally as rare but the distinction between engineering and button pressing (the manual labor) is absent.
To really prove that point many developers adamantly fear and oppose producing any form of original code. If you are terrified at writing original solutions to a problem how could the work possibly be considered any form of engineering? https://news.ycombinator.com/item?id=21883670