That's not the point though. Almost all futures traded are settled in cash. I've been trading futures for a living for the last 10 years, I've never taken delivery of barrels of oil, or cotton, or gold.
The point is that a legitimate futures market will allow major investors that aren't Bitcoin superfans, like most people buying bitcoins since its inception, a mechanism to short and drive the price of the Bitcoin futures contract down.
The a large dip in the future contract price will cause trader on the open market to slow down their buying of bitcoin, pause, or sell off to an alterative investment, this is where the rise of other coins will come in.
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