I think one hope with this ETF is that traders on the more public market (NYSE, etc) will be able to trade closer to the actual Bitcoin price in the short term. There was a time this year where GBTC was at a huge Premium (I believe upwards of 80%!) to the actual coin, which produces unpredictable results for short term traders. The ETF structure is often a very efficient way to lower discount/premiums, although using derivative products (futures) might also be unpredictable.