Well, the US is one exception in terms of software engineers salaries being so high. I work in Italy and a software engineer salary is at the same level of any other office job, or just a little higher, in fact most software engineered have a contract of metalworker ("metalmeccanico") probably for the fact that in origin most software engineering jobs were related to industrial machinery such as CNC and similar.
Sometimes a good worker in a factory can make more money, or a plumber, electrician, etc that has his small business will make more money, a truck driver will make (a lot) more money, etc.
Sometimes a good worker in a factory can make more money, or a plumber, electrician, etc that has his small business will make more money, a truck driver will make (a lot) more money, etc.