Earlier quoted context omitted.
They're not moving back into development. They're adopting a new approach of producing software, which has nothing to do with the work that software developers do. It's likely that they "left" the field because they were more interested in other roles, which is fine. So now that we have tools that promise to offload the work a software developer does, there are more people interested in simply producing software, and…
It's called being a systems analyst or product manager. Upskill into these roles (while still accepting individual contributor pay) or get left behind.
And an IC is not "left behind" if those roles don't interest them. What a ridiculous thing to say. A systems analyst or product manager is not a natural progression for someone who enjoys software development.