I don't know?

They're saying that programmers will be declining. While Developers, and crucially, Testers and QA people will be increasing. That testers and QA become more important in the future sounds plausible to me in a future hypothetical world of ubiquitous AI.

All of that doesn't necessarily imply that the Developer class of employees will grow at the same rate as the Tester and QA classes of employees.