If LLMs really can do a work of Juniors at least (even if Mediors or Seniors), the new skill actually is leadership. Managing, defining what needs to be done, why, how. What matters and what can be skipped.
I do not know if you have met an average employee, but even the good one suck at this. They can often barely manage themselves and their work and responsibilities. Managing a fleet of agents/people is unthinkable for them.
And it is not about people skills, it is about being organized, conscious, having a drive and clear vision.
Until LLMs can figure this out, we will not see 100x of anything.