My point was not that government is better or worse than corporate oligarchy in a question of governing. It's all the same people, same humans, just with different labels.
My point was that free market is kinda like unstable isotope, it can't exist for any significant length of time and will decay into a government. As soon as some corporation starts dictating its rules to an unrelated people, we can call it a proto-government. The department responsible for those unrelated people would be a proto-executive branch, the law department would be a proto-legislative branch etc.
And to address your second comment, about competition:
Competition can't work in the free market. The instant external control ceases to exist, the most shrewd and smart players would start employing all kinds of currently illegal shit. They will buy out all media and platform to blast their ads 24/7 and disallow all competition. They will swithch to currently banned practices and materials to save costs and undercut competitors. They will switch to slave work to save costs etc. As soon as one player becomes relatively bigger the rules of free market will allow him to accumulate more and more benefits of the kind I've described. Any competition would be woefully behind, outdated and overpriced relative to the bigger player. And that's assuming elastic market. As soon as market for some goods becomes inelastic, bigger player can do even more damage. For example they can completely buy out some resource or manufacturing capacity of a crucial component or resource and completely deny it to the competitors.
Basically the whole human history and law corpus is a list of examples how free market failed and how humans had to fix it via restrictions.