Hmm, they are already in development of more AI smart replacement limbs.
The other day on the news they were talking about these new robotic legs that were under development. the only problem with them is that the Legs were HUGE and heavy.
We already have the tech to make the prototype, but we have yet to make the smaller wearable stuff! "Oh, well!"
Truthfully, replacement limbs arn't that far off from from commercial use.
they have already developed a way to register brain waves even without directly connecting to nerve, but they can just use nerve connections anyway. All that's left is a power source and model...
That would be wonderful but for it to be like a part of the body you have to connect nerves to the item like the automail in FMA.And nerve regeneration and implating it on inorganic material is a long way but seem plausible.