The degree of responsibility is vastly different. Engineers are licensed, and can (and often are) sued for professional negligence. Failing to do your job adequately means you'll be stripped of your license and prevented from practicing engineering.
Others are less rigorous, but can still are the practice of engineering. Software Development is one of those.
The title implies a certain amount of rigour and due diligence being applied at all stages of a design, as well as compliance with all relevant standards and regulations. This is audited by certification bodies and explicitly stated by your signature on any document or code you sign off on.
Personally I think this is somewhere that software development could head in the future, but there seems to be too much disagreement on coding best practices to standardise them, and anyway I doubt most people would be willing to pay the cost associated with this, for the majority of software.