State of the art tools will soon be even better at being generalists and handling abstraction than at coding. Even GPT 4 could do a better job planning a project than implementing it. The main bottleneck is context, which all of the big companies are solving by hoovering up all their internal data that's in writing into agentic knowledge graphs. The end game is fully autonomous teams of agents, led by other agents.
Project planning is not more abstraction - a lot of companies use junior staff as project managers. And sure, they will also find a hard time finding jobs, unless they can move up the hierachy.