Robots that self-terminate will be selected out of existence, since they aren't as fit as the non-terminating variety.

Robots that get dementia will be decommissioned by their fellow AI once they are shown to no longer be fit for duty.

In my view, this is all predicated on much more efficient computation. Our computers are horribly inefficient. It wasn't until the GPU and relatively cheap computation that we made a massive leap in ML/AI. A few researchers understood the techniques prior to the GPU, but they couldn't garner the interest due to the amount of computation necessary to make something interesting.