I don’t see why a strong AI _needs_ to be trained specifically on reality. Imagine an alien race that sees world in X-Rays and neutrinos. An alien AI researcher claims that a “true intelligences” must train on the same inputs, and all those systems trained on the part of the spectrum between infrared and ultraviolet only fake intelligence.
I don’t see why intelligence has to be analogue in any way. Analogue systems are inherently noisy and contain limited amount of useful information, so you can always faithfully approximate them using digital representations.
If I am not mistaken Deepmind has shown spontaneous emergence of communication around 5 years ago when training agents in multi-player team shooters.