There were many ways Thanos could’ve killed Saitama He could’ve used the mind stone Saitama punch himself very hard or could’ve just use the soul take away his soul. they’re a bunch of ways Thanks could’ve killed him so I don’t think this is very accurate
Regular thanos loses to one punch man every single day but comic Astral regulator thanos solos one punch man,Goku,zeno and hyper sonic ar thanos has the power to erase others and get their ability when ever he thinks about it
one punch mans win becuase he is in another dimensyon but he can comeback like avengers.they to figt thanos and the winner is saitama even guko use hes ultra instict mui if he use that saitama use his tier 3