I agree, A fight between Goku and Superman that solely revolves around strength and speed without using Superman's weaknesses (whether he has the knowledge or not, or chooses not to for the thrill or fairness) is a win for Superman.
What bothered me were the mistakes they made. They said when using instant transmission he'd run into the risk of teleporting him to a planet with a red sun. All he has to do is teleport quickly to a few planets to find one. Before or during the fight.
Also, they said destroying the sun wouldn't matter because the supernova would destroy all the planets nearby completely dismissing instant transmission (If he'd have time for that is more a matter of opinion).
Then there's the way they calculated his strength and speed which I explained earlier why I disagree.
It's just hard for me to imagine someone with all the advantages he has over his opponent completely dismisses them and goes into a fist fight. I guess that's Goku then.
If we were to make a death battle between Buu and Goku, I'm sure they would have declared Buu as the winner. The only thing he'd need to do is teleport in front of him and turn him into an egg or something. No moral issues there.
Edit: I forgot about the kamehameha, like I mentioned before. We see Goku using it and destroying one single building with almost no effect on Superman at all. Besides it being massively underpowered there's just no way to calculate the effect a kamehameha wave would have on Superman (He would be able to hit him with it for sure using instant transmission like he did on Cell).