Is the letter published by the Federal Reserve real? The link in the article of the said letter goes to another bitcoinnews.com story about games in the cryptospace that is not related to this article.
In any case, is this another example of incomepetent reporting by the bitcoin news media or fud spreading?
It wasn't
The Fed like the article makes it sound. It was the Federal Reserve Bank of San Francisco. It was basically a research paper (done by their researchers and a Stanford professor), sort of in the vein of some of BitMEX Research's stuff.
I think there's some substance to what they're saying here:
We suggest that the rapid rise of the price of bitcoin and its decline following issuance of futures on the CME is consistent with pricing dynamics suggested elsewhere in financial theory and with previously observed trading behavior. Namely, optimists bid up the price before financial instruments are available to short the market (Fostel and Geanakoplos 2012). Once derivatives markets become sufficiently deep, short-selling pressure from pessimists leads to a sharp decline in value.
I think this was apparent in 2014 too. Bitfinex was just becoming a prominent, liquid exchange at the end of 2013, and it was the first place you could easily short BTC. Then came the longest bear market in history!
You can see BitMEX's volume rose similarly at the end of the 2017 bubble (and has only continued to rise since). I don't think it's a coincidence.
CME's volume is pretty high, so although there is no direct arbitrage, maybe people follow it.