It's a bit presumptuous to think a sentient AI/machine has to replicate the human brain. While there are complexities we still do not understand there are also

It's a bit presumptuous to think a sentient AI/machine has to replicate the human brain. While there are complexities we still do not understand there are also many shortcomings/defects that we do not necessarily need to replicate to a machine. One of the cognitive biases happen to be us thinking very highly of ourselves. Our brains are far from "perfect" (natural selection and all). While 2029 may be too early (note that it actually might not be. Nature doesn't exactly follow Moore's law, but so far electronics and computing do), I doubt it will be several hundred years. The other thing to keep in mind are geo-political event which may have adverse effects on scientific development/progress. To expect there to be relative peace in the next 15 years is a far better prediction than hundreds of years. We might even loose some advances by then.