Generally btc holders agree while short term up until 10th or so BTC may rise that shortly after a huge short will be taken by wall street hedges and price will fall greatly!
This is the first time I've seen this prediction. I'm pretty sure that BTC holders don't "generally agree" about this.
I also don't see why you assume that Wall Street will act in the specific way that you expect them to. They have quite varied views on BTC and eve the ones that believe BTC is in a bubble wouldn't necessarily short it.
So WHY WHY do the new billionaire brothers the Winklevoss's WANT a futures trade to happen?
Because they don't think the same thing that you've said. It's perfectly possible that it
could cause the price to rise, depending on who gets involved.
It's also possible that more people would get involved out of curiosity if BTC is introduced to more regulated and mainstream financial markets.