Originally posted by the Darkone
Thanos can react to fast moving objects, Thanos did had his physical abilities amp by Death. Thanos was reacted to Thor hammer and stopping it in mid-flight, tagging the Fallen One who was trying to speed blitz him, tagging a Silver Surfer. Having speed and reflexes doesn't guarantee you a victory, it takes more than that which Thanos has!!
Those things were not going as fast as Superman can move in a forum fight.
Thor doesn't generally throw his hammer very fast. Street levelers have dodged a hammer throw out believe. Firelord and Mangog has even swatted it away.
Fallen one is FTL at top speed, but almost everyone is. We judge speed on how fast a character can be in an instant. He was obviously speeding up when Thanos stopped him. We don't know what actual speed he actually reached when Thanos stopped him.
Next, those objects were much further away from Thanos than Superman would be in a h2h fight. Superman being more than 5x closer is equivalent to him being more than 5x faster than those objects (assuming that all move at the same speed). So those feats for Thanos are meaningless here.
Finally, the problem is not only Superman's speed, but his perception. He would view Thanos almost frozen in time. Using any sort of rational thinking, it is near impossible for Thanos to even land a blow. Superman would literally purposely have to have Thanos hit him.
Anyway, Thanos loses because of the speed deficit.