There are clear anti-trust mechanisms to prevent market capture and the emergence of asymmetric power. Go back and see how much nashing of teeth Lina Khan triggered in SV when she started to enforce antitrust law and then compare it to what the Pinkerton agency was doing in the transition from the guilded age to the progressive era.
There is a vocal segment of SV that wants the return of the guilded age. Marc Andreessen as said that explicitly. Those of us in SV that value free markets and recognize that the progressive era actually saved markets from their natural tendency to self destruct when winners capture markets and destroy competition that provides the incentive to innovate and drives the price setting function for efficiency.
In other words, the aspiring founders look at Google, Facebook, Tesla, etc. and think "how can I become one of them", not "how can I be different from them"? If you can find me examples of successful startups that think fundamentally different from those big techs, I'm very happy to be wrong and be corrected here.
I don't see any of such entity would solve that problem. The government and regulator are in OpenAI and Anthropic's pocket, and I don't trust them a single bit on coming up with regulations. The consumers don't care; they just need something smart and cheap. And the society doesn't work either: each person is too busy fighting for their own survival rather than changing the system.