In the absence of government intervention, wealth is more likely to tend toward the center. The issue is that any democratic form of government featuring any kind of legislature reliant on voting will be bought. First, large companies will want small little advantages like a new road to their factory. Overtime, it becomes massive like immunity from prosecution from drugs that kill people like opioids. Over time, these companies receiving benefits become indistinguishable from the government itself and drive nearly all policy like Boeing, Raytheon, Lockheed, JP Morgan, Goldman, etc. Generally, all attempts to stop this are subverted and used to the benefit of these megacorporations via riders on any such bill introduced by politicians who’re on the take. Further, the agencies tasked with enforcement of any regulation usually have people who previously worked at these companies or who hope to work at them in the future on their staff.

Humans respond to incentives, and all incentives line up toward the merger of corporation and state in a democracy. I’d like to see a free market democracy that lacks corporate personhood to see if that changes the structure, but a human life isn’t long enough to really witness such a thing.