I'm not sure we are in full agreement, my statement was a little ambiguous. I meant to say that, just like stack traces, Go error messages are only helpful to developers, at least 99.9% of the time.

More generally, user error messages and dev error messages are just fundamentally at odds, there is no way to have messages that are good for both cases. User error messages should explain what went wrong, and what they can do differently to workaround the issue (if anything). Dev error messages should explain what the code was doing when something went wrong, to help with figuring out what code needs to be modified.