Blackrock doesn't 'own' Tesla, or any company really. They hold and manage stocks for their customers. If you own an iShares ETF or mutual fund, you own the companies, not Blackrock.
I just don't think this is a practical argument. You have zero control, influence, or access to the businesses BlackRock controls. By contrast Larry Fink has the power, which he has regularly exploited, to reshape entire economies at the snap of his fingers, let alone just one of the many businesses under their control.
Which is exactly what investors pay Fink and the BlackRock team to do. Most people don't have time to analyze and choose things to invest in, so they offload that responsibility to BlackRock in exchange for some fees. The system is working as intended.
To me, the bigger issue is whether BlackRock just gets paid a fee to manage the portfolio composition, or whether they can also exercise voting rights on shares in their ETF.