Earlier quoted context omitted.
As discussed elsewhere in the thread, the few dozen keywords are a different matter (and are just memorized to mean "make the computer do ..."), but having useful error messages from your compiler helps get stuff sorted out more quickly. There are, to this day, people who get in trouble when their computers reply to them in English, including coding folks. I bet they were (and are) thankful for initiatives like yours…
Localized error messages are detrimental to solving the problem as googling the error message in a different language will prevent you from finding a solution in the main language.
Of course if you turn on localized error messages you might actually prefer results in your own language.