By the way, you've seen Cerebras? It's not gone as far as what you described - loads of cores and RAM but you still load up the weights onto it as software and they need to be streamed into the chip for large models - but it is a whole wafer.
They're pretty supply constrained right now though and their production costs seem prohibitive.
The interesting players at the moment are from Toronto: taalas (print the model onto the silicon) and tenstorrent (dataflow programming based hardware)
I suspect for equal performance, that's probably a 5x increase in silicon area (and therefore cost).