Why is depositing money in banks for investment purposes considered usury, while jurists differ on this ruling?

It cannot be said that there is no difference between Islamic banks and interest-based banks regarding investor deposits and the profits and interest resulting from them. Islamic banks invest depositors' money in permissible ways according to legitimate investment contracts such as Mudarabah, whereas interest-based banks borrow money in exchange for usurious interest. Allah has permitted trade and forbidden usury, and therefore, it is not permissible to claim that there is no difference between them.