Don't really know what to think about this...
We could have middle-class-state-blocked money being liberated to kind of migrate to bitcoin. That's the good part. Outsiders could have a chance to use their bloked savings in this.
In the other hand, bitcoins could be much more centralized than today, and supply would be increasily limited (reminds me Dash). Price would rise, but also, fragility of the whole system. One Nakamoto with 1MM is enough, in my opinion.
This ETF thing is not over. In the future there will be new attempts to dominate this. Let's hope the size of bitcoin will be huge (like 10x of now) to absorve all of this.