> It becomes a meaningless word if anyone can just call themselves one.Only to the extent that all words are meaningless. However, we keep a reference known as a dictionary that helps maintain some consistency around meanings of words.
The Oxford Dictionary defines engineer as:
1. A person who designs, builds, or maintains engines, machines, or structures.
2. A person who controls an engine, especially on an aircraft or ship.
3. A skilful contriver or originator of something.
Is software an engine, machine, or structure? That is debatable, although I would suggest that it does meet the definition of machine. Under that suggestion, software engineer is a perfectly appropriate term. Designing, building, and maintaining is exactly what software engineers do.
If you disagree that software falls under the definition of engine, there is still that third definition. Is software created by a skilful contriver or originator of something? I think that is a definite yes.
> There has to be some standard, some governing body, some degree of rigour applied here.
Professional engineers are expected to display those things. That is unrelated to engineers. Different terms with different meanings. Software engineers may not be professional engineers, although they can be.