> The AI would have to be omniscient as well as super-intelligent to devise the optimal society.
This is pure conjecture.
1) nothing needs to be omniscient, it just needs the same data we already have. AI has already proven better at synthesizing complex data than humans in many cases. So even existing shitty AI can improve on many things given just the data we have.
2) Neural networks and genetic algorithms for example don't contain any intelligence at all, yet they solve many problems we have not been able to.
Also "optimal society" isn't right. Sure, a "perfect solution" needs perfect data, but we don't need it perfect, just better.
And our current stuff is far from optimal. Back in Taylor's day factory owners probably thought they were the epitomy of efficiency. Yet Taylor just applies some numerical comparisons, and increases efficiency by orders of magnitude, without needing to make people work any harder. Taylors reductionist system, breaking down tasks into steps, seeing who was fastest at each step, them reassembling the steps into a new process. That's basically AI (an early genetic algorithm basically, since people will adapt each "best step" further by themselves and you can do multiple iterations of the Taylor process), the data analysis determined the design of the new process, not a person's judgement. The existing "experts" - people who did those tasks day in day out professionally for years were beaten by maths. This lead to a quantitative change - higher output, but the long term effects of that are qualitative change, changes to the way of life itself, since new products become commerically viable for the general population due to higher productivity that would have been impossible before, or have been luxuries only for the rich before that.
I think we're at a similar situation to the 19th century before Taylorism, where people think we have things pretty nailed down so computation couldn't come up with anything significantly better. But most of our systems are ad hoc systems stitched together with no real deep meaning except making things easy to comprehend in terms of the pen-and-paper beareacracy days. Even our computer databases are basically automated versions of pen and paper record keeping. Things are so ad-hoc basically, that it would be a miracle if numerical analysis couldn't overhaul our systems to be radically more streamlined and efficient.