It is the additional exposure. Previously it was really just Grayscale but not we have what roughly 10 ETFs so there are more people who are getting into it this way which is good in that people are accepting it as a part of the future but when the market tanks an ETF holding BTC only would be the first on the chopping block. Esp if people are for instance facing the good old Friday margin calls and are having to firesell the newest and most unfamiliar things will be sold off first so BTC gets some additional downward pressure if that makes sense.