I think more importantly than the ratio, is the qualifications needed for each job. You might be killing jobs for the less intelligent people of your society and create jobs for intellectuals.

One has a hard time going from a manufacturing job to a programming job.

That may be true initially. While adoption is low, the overhead labor costs per unit are relatively high. But even here, as you scale out, your overhead costs per unit get much lower. Eventually the labor cost to build one robotic arm will be less than labor cost replaced by the robotic arm.

If this doesn't happen, then its not more efficient.

I'd suggest the opposite: it's entirely possible that a factory of human workers can create robots which massively scale the production capability far beyond the original size of the factory's employees.