I'm underwhelmed. The reason we build our programs that way is that actually makes them less likely to crash. We actually have access to programs structured more like the E. Coli graph. They crash a lot. Because the fact that one error takes down the whole system has less to do with the organizational structure of the code, and more to do with the fact that we've deliberately built the system such that one error will crash the entire system... because the alternative is worse. There's no recovering from a segfault not because there aren't enough different implementations of core functionality, but because there is no sensible way to recover from a segfault.

Cells have a type of redundancy programs do not have, and may never have, and it actually hasn't got anything to do with the source code at all. They have numerous independent copies of things that mostly work, most of the time. They perform tasks that transform lots of things into lots of other things, most of the time. The whole system is built so that everything mostly works, most of the time, usually recovers, and it doesn't matter much whether this cell dies or that mitochondria malfunctions. It's an entirely different set of primitives brought on by massive parallelism. (And not the usual biological parallelism you hear about in the brain, but physically, everywhere.)

It's the difference in primitives that brings about the difference in result. Difference in optimal layout is an effect, not a cause. Cells don't have the option to work like programs, and programs really don't have the option to work like cells. (At least not without a lot more computational resources.)