The company doesn’t “define the center,” or endorse specific viewpoints. It measures the polarization of its network, and where pockets or filter bubbles start to form, it cross-fertilizes the user’s feed with content that tends to smooth out that cluster. The algorithm isn’t targeted. It doesn’t know who it’s interacting with. Its just knows that there’s a cluster there, and perhaps the mood or intensity of its users.
Ad-driven algorithms that parrot your opinions back to you in progressively more extreme forms are far more dystopian than one that simply tries to expose you to new people and perspectives—which was, after all, what the Internet originally promised.