There is no way that the SEC approves any kind of ETF for the foreseeable future. The most recent rejection (the one everyone was convinced would be approved) was rejected citing price manipulation concerns.

The problem is cryptocurrency is not regulated. There is nothing stopping a kid from going onto Twitter and tweeting out a false announcement or hype. There is nothing stopping a group of amateur fraudsters from creating a pump and dump group, then doing coordinated trades on exchanges to artificially raise and lower the price of different cryptos.

The price manipulation problem in cryptocurrency will not be solved for a very long time, if ever. I can't ever see the SEC approving an ETF unless some kind of regulation is introduced to make price manipulation of cryptocurrencies illegal like traditional regulated markets.