And that's the problem right there! It is still Blackrock buying bitcoin not the customers. That means you can't go to Blackrock and demand they give you the bitcoins they bought on your behalf. And at some point they may not even buy any bitcoins with your money and yet take your money all the same...
Exactly.
But I don't see need for panic as Blackrock is buying more BTC for her investors. They are in the market for profit making, giving room to the public (clients) to invest in the market with the fate of making profits off there investment, thus can lead to bitcoin rise overtime because of more players into the market and the concept of supply and Demand.
Only few of the general public have understanding about how bitcoin system works, and the implication of investing in Bitcoin market through a third party system which is the only reason some members of this forum careless.
No doubt we all believe and practice Self-Custody but most new players don't really understand and would rather prefer investing with big investment Company like Blackrock.