Wills was a contender for like a decade and was pretty big and strong even by the era's standards. Could he have won the belt and if so, when and against who?
Harry Wills certainly had the skill and toughness to be competitive in the 1950’s. But weather or not he becomes a champion would depend largely on how he adjusted to the rules. Floyd Patterson, Ingemar Johannson and an aged Joe Walcott would all be men he’d have a chance at beating. Marciano isn’t out of the question but he’d be more difficult
In his prime, and with a modern training schedule (having camps and not fighting twice a month) I dare say he would dominate that era.