I don’t think this is a problem caused by centralization. As I think about the past 4 years I think the blame lies with Congress, whom have effectively gridlocked themselves into inaction for the last decade. The powers that they have have already been spilling into other branches (such as using the courts to audaciously overturn laws) so it makes sense that those powers are spilling into the private sector as well.
In other words, the less Congress does, the more easily corporations turn into an authoritarian arm of the government
In other words, the less Congress does, the more easily corporations turn into an authoritarian arm of the government