False. One of the many contradictions of Capitalism is that it assumes complete uniformity in many respects - for all of its focusing on on individualism.
The sweeping assumptions, such as “uniform human nature”, and the necessity of uniform ability, uniform perfect knowledge and mobility - in order for perfect competition to come even close to arriving and all that… it is not just Totalitarianism that needs human equality in order to work. And then you factor in the refinement of the best worker attitude that it is necessary to fake in order to be employed and remain employed, and the necessary “type” that one needs to be a member of in order to compete in the employer respect. You won’t hang onto your inherited riches if you don’t have it, and you won’t “earn” any riches if you’re poor and aren’t the right “type” of person.
In short, it is necessary to remember that there is no “human nature”.
Humans vary, sometimes significantly. If ever a large proportion of people take care of their own self-interest first, others do not. And of course there are environmental aspects that bring out self-centredness where there would have been none under different environmental circumstances. It’s easy to make sweeping generalisations when you live under an economy that rewards only self-centredness and hinders more altruistic behaviours - meaning selfishness is nearly all you see. But even under such economic conditions, there are still plenty who are not primarily self-interested. The natures of humans are extremely varied with much potential for adaptation. To treat humans otherwise, as classical liberals and neo-liberals do, is a great tyranny - for all the “freedom” that their ideas are supposed to celebrate.
We have. If even the disaster of Chile under General Pinochet is denied as a “real” free market, it is the closest we have seen to one.
For the sake of going with those who deny this is an acceptable example, we see examples of “free” economies anywhere else in life that isn’t human. They result in a harsh, unforgiving life where the weak literally die out and only the strongest survive - and even then they don’t survive for long without the organisation of more centralised planning. This is the default situation for all “free” economies - a regression back to the animal. Humanity is indeed defined by its ability to plan its economy, and its history in doing so is such that it came to dominate all other forms of life on earth.
Minarchist versions of Capitalism simply outlaw force and fraud, which are by no means the only ways that cause the weak to literally die out, leaving only the strong to survive a stressful and shortened life - due to the lack of emphasis on wider social cooperation. Planning beyond such minimal measures to moderate “real” free market Capitalism is the only thing from stopping black markets from proliferating everywhere selling all sorts of socially detrimental products and services.
The “real” free market denies humanity its greatest and most defining strength, and leads to faaaar more death, human misery and suffering than what we are used to (just as the far right, which must not be confused with “real” Socialism and Communism).
There is a fiction amongst Capitalist defenders that all planning is detrimental to freedom and prosperity - except of course their own private planning that is concealed from other private planners who stem information flow for the sake of such privacy and all the “competitive advantage” that this affords them… and the fiction that such private planning is all about freedom, with no negative side effects whatsoever…
The primary negative side effect of such ideology is the very real dichotomy between capitalists and wage labourers. The capitalist must always desire more from the wage labourers who sell their labour to them - obviously this increases the profits that are the whole incentive, which is somehow deified as the only incentive that really causes people to innovate and work their best: a materialistic incentive. And the wage labourer must desire to keep the capitalist demands upon them to human levels - in as as far as they can, which isn’t very far because of all the threat of the huge pool of unemployed people out there, gunning for their job.
Capitalism is not without the threat of physical force - it’s just monopolised in a Minarchist State or privatised under Anarcho-Capitalism. If you don’t play by the rules, or you’re too poor to do so, you certainly feel such physical force.
There is a lot more to Leftism than having a bleeding heart and a vengeful desire to control the “bad/evil/selfish/wrong” people.