Cerebras is a whole lot of SRAM, basically a ton more L1/L2 cache, hence increasing throughput.

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)

There is a huge downside to weights being modifiable - it means you need to have multipliers (not simply adders), and SRAM to store those weights.

I suspect for equal performance, that's probably a 5x increase in silicon area (and therefore cost).