No, it's not the same. An uncapped downside would be something like shorting stock. The price of the stock can be unbounded, and you owe the difference between

No, it's not the same. An uncapped downside would be something like shorting stock. The price of the stock can be unbounded, and you owe the difference between the current stock and the price you opened your short position. So you can literally lose an unlimited amount of money.