I do agree that software development is many parts engineering, but I believe that farming is engineering to the same extent (I do both, so I have an intimate knowledge of how they compare). Imagine a farmer calling himself an agricultural engineer.
It is part of the nomenclature now, so it is what it is, but I don't see what was wrong with the previous "programmer" or "software developer" titles. The engineering part was already implied.
Indeed, in some countries (like mine) calling yourself an engineer while not having the real degree it's illegal, even if it's your job description.
Incidentally, here (Argentina) we have the equivalent of farming engineer, called "Ingeniero Agrónomo". It's a very common career choice, and well paid.
It is part of the nomenclature now, so it is what it is, but I don't see what was wrong with the previous "programmer" or "software developer" titles. The engineering part was already implied.