Wikipedia: " Historian Doyce B. Nunis has said that the Spanish named it 'El Pueblo de la Reina de los Angeles' ('The Town of the Queen of the Angels'). For proof, he pointed to a map dated 1785, where that phrase was used. Frank Weber, the diocesan archivist, replied, however, that the name given by the founders was 'El Pueblo de Nuestra Señora de los Angeles de Porciuncula', or 'the town of Our Lady of the Angels of Porciuncula.' and that the map was in error."
Neither historian claims that the original name was simply "Los Angeles".
Although it wasn't always called by that long name, but the thing i considered was that LA's name wasn't "changed", it was "abbreviate". But NY's name was "half" "changed".
The previous name of New York was "Nieuw" Amsterdam, not "New" Amsterdam. English language quiz or not, write the correct previous name for the city. (Note: You don't anglicize Los Angeles).
Neither historian claims that the original name was simply "Los Angeles".