Somebody did a video of that actually, and while DBZ fanboys might rage about their decisions, I think I agree with their basic ideas. Their idea is that without either of them knowing the other's weaknesses ahead of time Superman ends up "winning" due to a basic thing. While Goku has the Saiyan ability to break any limit placed on him, Superman has no limits. Superman's story has always been one of infinite power pushed into an immigrant scenario, while Goku's has been one of meeting a limit, smashing his face into it, and training to overcome it.
It's like comparing "infinity" with 1+1+1+1+... Sure, they both go on forever to the point that comparisons are worthless, but if you ever pause at any given point in the addition the infinity will always be greater than the series. At "best" you get a situation where Superman is constantly beating Goku into the dirt, but is unable to ever finish him off completely because Goku keeps leveling up. The battle would never really end, but there would never be a situation where Goku was "winning" or even "equal" with Superman, because the only way for 1+1+1+1+... to equal "infinity" is for the addition (the battle) to go on for an infinite amount of time.