A full wafer like Cerebras is about 60x that, and N2P has about 3x the transistor density. So right now it's technically feasible to etch a 1.4 trillion parameter model. So roughly DeepSeek-V4-Pro class. Imagine that running a factory, for example.
Etching failure in that situation would be like brain-damage in a human, all sorts of weird effects would start appearing.
(Is Cerebras doing something novel? CPUs and memory blocks have been doing those things for a long time too, since the error rate is otherwise too high for normal size chips as well)
[1] see eg https://www.vlsimentor.com/dft/redundancy-bisr to get some basic concepts