Just my opinion based on observation. Just like everyone else's here. He did take out the moon pretty easily though, before even going to Namek or fusing with anyone.
Could Superman from the movies one-shot the moon? Oh wait, according to you guys, that superman never happened / doesn't exist. DC ended the Superman lore in the 50's when the Silver Age of comics ended.
The difference is consistency. Again, everyone who *wants* Superman to win, focuses only on Silver Age Superman, as though there aren't dozens of other incarnations that would lose to Goku, rather easily. I've already conceded the fact that Silver Age Superman wins this, not sure why you guys are still going on about a supernova and a dude who sneezes out universes when we already agree on that. I'm just waiting for someone on the Superman side to acknowledge that if we talk about any other version of Superman, that Goku takes this.