Earlier quoted context omitted.
I think that's actually the effect of anti-trust/anti-monopoly laws. There's a point where companies get "too big to fail"/"too big to jail" and have outsize effect on the country (especially if the country is stupid enough to pass a Citizens United law that explicitly allows them to do this). Anti-trust laws are the main way that the government tries to prevent this, and haven't really been used since Reaganomics de…
With only a passing knowledge of the field, I'm aware that the standard of monopolistic effect varies between the EU and US (neither specifically uses financial size as the standard). In the EU it's about whether there is sufficient competition in the market, whereas in the US it's about whether the price is sufficiently competitive.
It wasn't always like that, though. We used to have antitrust with serious teeth in this country. And then it literally got borked: https://en.wikipedia.org/wiki/The_Antitrust_Paradox