Superman beats Darkseid, because he is top tier.
Thor can't beat Thanos.
The implication then, is that Superman > Thor.
That is why people can't accept it, they will fight tooth and nail, just as they fail to register Thor getting knocked out, whilst accepting Superman's dubious claim that he MAY be the toughest opponent he fought.
But Thor did defeat Thanos.
Sure, it ended-up being a clone, but Darkseid too ended-up being an avatar.
The avatar idea got explored even more deeply in Death of the new gods when we learned that we never actually met any New Gods ever.
I just don't get it. Why such a different perception and treatment.
though frankly I really disliked the concept....it seems to undermine a lot of continuity IMO, but that is a fair point.
I still hold that Orion's avatar showed he can engage Darkseid's avatar on roughly equal terms.