broly is the true legendary super saiyan as he was born a thousand years after the last with unprecedented powers unlike Goku. And the golden great ape isn't considered canon because GT isn't considered canon. Both Broly and the Golden Great Ape are considered non canon as they were not made by Akira Toriyama nor were they in the original manga. In canon terms, Goku is the Legendary Super Saiyan... but then those like Vegeta and even the half breeds like Gohan, Trunks, and Goten becomes Super Saiyans as well.