None of the advances in software development have eliminated software development. Hell, there are still job openings for COBOL developers. CI hasn't resulted in a whole swaths of people suddenly out of work because they were running tests by hand and now there's nothing else they can do.
Now, extend that to salaried positions. There is a certain amount of work that must happen. Tooling improves, devs become more idle, management consultant fires one (over time).
This has been somewhat negated only because the role of computers has been growing quickly and outpacing the growth in efficiency. That will change at some point. As you said, there won't be a case where swathes of people are suddenly out of work, it will be gradual.
A guy I know is an economist and does consulting for factories to optimize production. He has talked about how some areas these days have removed large groups of humans and replaced them with single humans observing machines. Eventually, development could reach a similar place.
In some cases, if productivity increases, and the price performance follows, we will consume far more of a thing, growing the market and employing more people.
Of course it does. Not on an individual level, but if suddenly one employee can do three times more work, there is no need to recruit 2 more full time jobs to address the increasing needs. So on the whole, productivity will destroy jobs, but the good news is that the additional returns will create other jobs in other areas.