You’re going somewhere that Fink didn’t, in my view. He said this:
“Society is demanding that companies, both public and private, serve a social purpose,” Fink wrote in his letter, a copy of which was shared with CNNMoney. “To prosper over time, every company must not only deliver financial performance, but also show how it makes a positive contribution to society.”
Fink said precisely nothing about Blackrock becoming a “social investor”; he’s simply stating a broader view of what the responsibility of a corporation is, compared to “shareholder only”.
I would tend to doubt that this implies that Blackrock is going to engage in “socially aware investing” like specially designed funds for that purpose (some of which do quite well, compared to benchmarks) do. Fink is simply providing the counterargument to the Friedman Doctrine, which most large corporations rejected quite a long time ago.