The show showed Stringer was wrong literally at every turn.
He tried to run the crew like a business, then flips out on Poot, snaps into gangster mode and undermines his own thing.
He tried to run his business like a gangster, bribing folks and cutting corners and got rain made, then doubled down by trying to assassinate Davis before getting sat down by Avon.
He tried to run the co-op like a business by trying to school Marlo instead of taking him out. Marlo took that as a sign of weakness and went directly at Stringer.
He is always shown to be wrong in explicit detail. Like it's not a debate, the show spells it out over and over (and over...) again. He is a colossal fuck up who loses in business (getting his money took and getting nothing in return) and loses in the game by getting shot up by 2 people he had tried to play.
That he ends up shot to death in his own building, his 2 world's having collapsed on themselves should be evidence enough but people see what they want to see.