These are all valid point if documentation is the only way to get the info. They key point to me in TFA: "The feature is a black box" This doesn't apply to so

These are all valid point if documentation is the only way to get the info. They key point to me in TFA: "The feature is a black box" This doesn't apply to software internal documentation. It's not a black box and you can give any deep you want to know what is and isn't implemented, what has explicit tests and who wrote it. Whether comments on those are a waste of time of not will come down to how long it will take to write useful comments, how long it will take for the reader to understand the class/function/method otherwise, how much maintenance will happen on the comment itself after it's written, what it will cost when it will "rot", and what else (e.g. tests ?) the dev could do with all that time.