Better IDEs have saved countless hours. Saving hours is equivalent to replacing jobs, unless demand is elastic enough to fill that time. Most of the time we are lucky enough that demand at a given price point is much larger than supply, but this won't last forever.
that's not how it works... as it is not a zero sum (i.e. the work is not bounded/fixed but it increases).
IDEs and higher level tools help engineers become more productive. They can do more, with less. This raises the bar on products, and the demand of customers for them (things are pretier, easier to use, etc..), which in turn creates more domains for software to be used, and more demand for engineers.
