BitCoin was developed as a currency from the begining. Just look at its name bitcoin, and the paper that originated them "bitcoins: a peer to peer cash system".
That something is intended to become money does not necessarily mean that it is money.
Transaction privacy is a monetary utility. Costs are irrelevant for market value, I could spend lots of energy and work to produce something that nobody wants, so no matter the cost its market value will be 0. Market values drive costs, not the opposite.
Not it is not. It is payment service utility.
Yes, but you would not place the first sell offer in the market at 0 but probably at your cost or higher unless you where really stupid.
But I claim that Regression Theorem is not necessary, and it does not work not only with BitCoins, it doesn´t explain well why credit currencies have value. Carlos Bondone´s monetary theory, which is based on Austrian School founder Carl Menger,proposes a stronger monetary theory, which prefectly explains the BitCoin phenomeon and in regard of this theory BitCoins do qualify as money.
It does explain why credit currencies have value. They are initially issued in promises of X that already have a market price. So there is plenty of regression there with a very strong link to previously established prices. Bitcoin has a very weak link to previous established prices but provides additional payment service utility which has value in itself.