Wait, how is that actually different than what our brains do?
From what I know, our cognitive system is built in quite a similar fashion of probabilistic pattern matching with backpropagation, coupled with some "ad-hoc" heuristic subsystems.
Eh no. Our brains and how human mind works are actually very poorly understood. To claim we have a good idea how our cognitive systems work under the hood is an incorrect statement.
there is nothing like backpropagation in the brain, or a probabilistic pattern matcher. there is evidence that a connectionist model is applicable, but learning is not deciphered, and there are aspects of it, like neuronal excitability, local dendritic spiking, oscillations, up and down states etc, which do not translate at all to DL systems. That said, the increasing success of connectionist architecture does point to the conclusion that the brain is also a connectionist machine.