There are a lot of good comments above, but also mixed in with nonsense and a fundamental misunderstanding of the dynamics of Bitcoin.
Are biggest financial players in the world slowing and stealthily making a move on Bitcoin? YES.
Blackrock, China, Soros, Goldman, etc and many super private but powerful HNW's. Yes, of course they are.
Will established players in finance seek to take over the space from startups? Yes, of course.
How can we defend against this (or benefit from it?) That of course if obvious ... BUY BITCOIN AND HODL.
Is the fact that Blackrock and others are moving into this space a bad thing? Does it reduce the power of the de-centralization of Bitcoin? This is where the nonsense comes in. The fact that Blackrock and other established institutions are entering makes no difference to Bitcoin. Bitcoin keeps doing what it does. It does not care who owns it or how much of it you own. Unlike Eth (or other shit coins) Bitcoin cannot be controlled dependent on the stake of it that you have. And game theory, basic economics, and mathematics dictate that no single player can keep infinitely acquiring it, as to do that requires sellers, and because supply is limited, more demand will equate to ever increasing prices.