Or the first guy is using it wrong and taking the chance of introducing even MORE bugs (more cooks in the kitchen) while the second guy is relying on code that has been tested time and time again, not only by the Mathworks, but by all of their customers as well. Tell me, when writing code for Linux do you re-evaluate every line of the kernel or treat it as a black box?
One of our largest customers (a Fortune 100 heavy equipment manufacturer) relies on generated code to control their engines. And these are big engines. The Mathworks produces very solid code allowing developers to create control systems very quickly that are time-tested to be reliable.
That being said, that doesn't mean Toyota simply didn't connect the blocks wrong in this case. A human is still responsible for the logic.