It can be bought, in fact by anybody, including a potential attacker. The attacker could even be a group of miners on the current chain. How much would Blackrock be willing to spend to secure their new chain? Even if they did that, would the new chain retain the same value proposition if the code changes were nefarious or closed source? Reminds me of the hash wars, except the network is an order of magnitude more secure than it was during the hash wars.
Discussion
Sadly I have this quote by Silvio Berlusconi spinning in my head these past few days, it is tainting all of my thoughts.
“See that group of 100 people there? How many of them do you believe are intelligent? 10? I take care of the remaining 90%. “
The remaining 90% will actually decide.
Crypto ownership stands at around 4.2% worldwide. Some do not even own Bitcoin.
A lot of truth to that quote. Good thing btc is not proof of stake, so we don't have to worry about the votes of the fools. At the end of the day, while I agree that one possible attack vector is a contentious hard fork, it's something we have already been through and the network is much more resilient than it was at that time. Blackrock is much more potent of an enemy than the big blockers were though.