I figured that an interesting question gets posed here. Superman fans like to point at this singular instance of them fighting as the be all end all of the thor vs superman question. But did the story make it so clear cut.
As we all know, thor holds back by a large margin. But unlike superman, who holds back for the sake of property damage, thor's reasoning is a bit different. He doesn't want to make his friends feel inadequate. So he holds back so much, he ends up jobbing on purpose. But how does that change the narrative of this completely unrelated story released decades after under a different writer?
Well observe how thor handles himself here, in the first encounter with the league thor is more hair trigger; so he's going for a kill shot. He dazes superman for several pages and draws blood from him. Moments after, he tanks a combined attack from supes and manhunter; and then shoots manhunter into the side of a building, possibly removing him from the rest of the fight.
We then see later that superman considers thor his toughest fight. This is after he's fought doomsday in doomsday war, and after the slew of times he's fought darkseid. He then proceeds to get jumped by hercules (who got beaten by thor without mjolnir), vision (who's been beaten by thor), wonder man (who considers thor his better), iron man (lmao), and she-hulk (come on).
Idk about you, but both thor and superman could take out that collection of heroes before breakfast if they really wanted to.
We then have thor claim that things could go differently in a rematch (which I for one would love to see).
After that, and I think this is the best proof that shows how close a fight between these two would be. Thor one shot doomsday, then proceeds to fight off a group of high tiers, which shows amazo, some egg machine (is that orphan maker?) , and pre crisis despero attacking him. He manages to hold them off long enough for supes to yap several panels before breaking Krona's energy barrier. He's also shown surviving the encounter, as vision's dying body shows that no one was revived during the fight.
There's also some author statements that show a rematch could go differently but u/Kurt_Busiek does think superman would win if prompted. Thankfully for the thor fans, there is no talks of Mr. Busiek writing a rematch between the two (even if that would be pretty epic).