Totally agree, which is why nobody is suggesting adding the background and reasoning behind the change to the source file as a comment. They are suggesting add

Totally agree, which is why nobody is suggesting adding the background and reasoning behind the change to the source file as a comment. They are suggesting adding a more informative error, which may include a subset of that background and reasoning. An error message that points you to the functions you should use instead is infinitely more informative than one that says “this is banned. Bye.”