The von Neumann architecture is not ideal for all use cases; ML training and inference is hugely memory bound and a ton of energy is spent moving network weights around for just a few OPs. Our own squishy neural networks can be viewed as a form of in-memory computing: synapses both store network properties and execute the computation (there's no need to read out synapse weights for calculation elsewhere).
It's still very niche but could offer enormous power savings for ML inference.