If I see the SpaceX code, and it’s full of thousand line functions with a cognitive complexity of 200 I can confidently say it’s going to be hard to maintain.
Clearly it gets rockets into the sky, but something similar is true for all code that hasn’t failed catastrophically yet.
Except you would be wrong. Or at least not obviously right: safety critical code does all sorts of weird things in the interests of verifiability because it must be exactly right: it doesn't get "maintained", because once it's flight proven you do not change it without an entirely new verification process.
This also leads to interesting practices at times like favouring repeating code over writing separate functions to ensure the flow of reading doesn't jump around and instead always moves forward.
Is there any reason to suspect that Twitter's code will be of this terrible quality? If not, then again: what's the point of bringing random engineers in to take a look at code from an entirely unfamiliar domain?
Clearly it gets rockets into the sky, but something similar is true for all code that hasn’t failed catastrophically yet.