Broly’s raw power in 'Dragon Ball Z' is honestly terrifying—like, the guy turns planets into confetti just by flexing his energy. But could he actually kill Goku? It’s a messy debate. In 'Broly: The Second Coming', Goku’s dead (literally, he’s in Other World), so that’s a weird technicality. But in their first clash, Goku needed help from his friends to win, and even then, it was barely a victory. Broly’s strength scales insanely, but Goku’s adaptability and technique might edge it out. If it’s a one-on-one, no interference fight? Broly’s rage could overwhelm Goku before he pulls out Ultra Instinct or some new Saiyan trick. But Goku’s plot armor is thicker than Broly’s muscles, so… yeah.
That said, 'Dragon Ball Super' Broly is a whole different beast. His controlled power in the movie makes him way more dangerous than the OG Legendary Super Saiyan. Goku and Vegeta barely survived that fight, and that was with fusion off the table. If Broly went full lethal, no holding back? I’d bet on him. But Goku’s always got a last-minute power-up lurking, so it’s never a sure thing.