Re: existence of an ETF, it’s the only way to “hold” BTC (or ETH) in an account with tax advantages (such as TFSA or RRSP in Canada, equivalent to Roth IRA and 401K in the US respectively).
Proponents think it will collapse the dollar and bankrupt all governments.
Opponents think it's negative-sum and the sooner cryptocurrency dies the better for industries that actually create value.
Either way it's a (mild) attack on effective government and civilization more generally. The less subsidies for traders the better, from the perspective of a currently-influential government.