This hits at one of the core flaws of libertarianism. They tend to hold as a core axiom that competitive markets and free markets are one in the same, i.e. that the "natural state" of the markets are highly competitive, and if there is a lack of competition, it must be an "unnatural state", i.e. there is some sort of top-down interference, government policies, which restrict competition.

Libertarians thus see cronyism as happening from the top-down, where governments interfere with the markets, create monopolies, and all for the purpose of enriching themselves. Hence, they conclude the problem is government, that you have to get rid of government and then the problems will be solved.

This is the direct opposite view of Marxists. Marxists instead argue that markets inherently lead to a gradual increase in monopolization over time, what Marx referred to as the "laws of the concentration and centralization of capitals", and that market economies have a natural tendency to move more and more away from competition over time.

More than this, Marxists also see political power as not ultimately originating from the superstructure of society (the politics), but instead from the base of society (the economics). Any government policy requires enforcement, but any enforcement inherently presupposes an economic system which can produce tools of enforcement and allocate them appropriately to the enforcers. Politics is inherently derivative of economics.

The reason the political system favors the wealthy is not because of some laws implemented by some evil cabal that if they were just abolished, then capitalism would "work". No, the reason the political system favors the wealthy is because the wealthy are the ones who control society's wealth, and so of course the political system will favor them.

No law you write on a piece of paper will make a billionaire like Jeff Bezos have equal political influence as a minimum wage worker barely making ends meet. Production is the most fundamental basis of human society and those who control production control society's wealth and will inevitably have more influence. Even if you write laws saying bribery is illegal then they can just bribe those who enforce it.

Hence, Marxists do not see cronyism as a result of top-down processes implemented by a corrupt superstructure, by some evil cabal within the government that corrupted "true capitalism" and turned it into cronyism.

Rather, Marxists see cronyism as originating from a bottom-up process, that stems from the economic base in and of itself. Markets inevitably lead over time to greater and greater monopolization, creating a larger and larger gap between the working masses and the capitalists, and even if there is a "rising tide" and workers' wages rise as well, the profits of capital increase disproportionality faster, and capital continues to centralize rapidly, leading to an increasing social chasm between the rich and the poor.

This is why libertarianism/conservatism has never worked in history and will never work. They can't get rid of "big government" because the economic base, capitalism, inherently creates an enormous social divide, enormous polarization in the economy. This enormous wealth inequality naturally translates to power inequality, which then allows the capitalists to capture the state for their interests.

Once the capitalists capture the state, there is no reason for them not to implement "big government" but for their own benefit, i.e. corporate bailouts and subsidies and such. Libertarian policies, hence, in practice, always lead to "big government". Never in human history have they actually achieved their goals, because their goals are fundamentally impossible and self-contradictory.

Another separate point is that these people also have a tendency to water down what "capitalism" means. Capitalism is about capital, that's why it's called capitalism. This refers to a specific kind of society dominated by capital, i.e. production for profit. Libertarians like water down "capitalism" to refer specifically just to trade or markets, but capitalism is not tradeism or marketism. It's capitalism. Pre-capitalist economies have had trade and markets and so have socialist economies.