In almost every industry the bottom is subject to shifts while the top with most ability and experience tends to be secure in their jobs.

If the industry shifts needing less developers (for whatever reason), companies will just set higher expectations when hiring meaning a lot of people will not be able to find a job.

But I don't think this happens. Copilot is not going to solve development problems same way stack exchange and google did not. We got google and se and number of developers only grew.