[antidesitter]

> A free market is one in which, once uniform or standard rules or requirements are established

This is not correct. A free market is a market that is free from government interference. Such rules or requirements can constitute government interference. Ergo, they can fail to yield a free market.

To see the absurdity of the claim that "uniform or standard rules or requirements" always yield a free market, consider the "uniform rule" given by the price floor I described above.

> Even within a so-called free market, numerous market failures may exist

This is irrelevant to a discussion about whether the term "free market" is meaningful. It's moving the goalposts.

> coercion, fraud and misrepresentation, capital concentration, systemic risk, capture and corruption, numerous parties unable to participate in wholly market-based transactions (?)

These are not "market failures", and many of the failures you described are really the same (Gresham's Law and information asymmetry). That aside, one must take into account whether the alternatives are worse: in other words, government failure. For example, on your point about "rent-seeking and rents":

Alexander Hamilton of the World Bank Institute argued in 2013 that rent extraction positively correlates with government size even in stable democracies with high income, robust rule of law mechanisms, transparency, and media freedom. [1]

> What you're describing

What am I describing?

[1] Small Is Beautiful, at Least in High-Income Democracies: The Distribution of Policy-Making Responsibility, Electoral Accountability, and Incentives for Rent Extraction. Alexander Hamilton. http://documents.worldbank.org/curated/en/195551468332410332...