Summary: All proposed alternatives to the current socio-economic model are failures due to the inability of these models to account for basic societal forces stemming from a general desire for the accumulation of material wealth. Often this is due to a myopic view of the present which does not succeed in tracing behavioral tendencies down to root causes.
For the sake of simplicity, this argument will be contained to the western countries of classical heritage. That is, countries who all exist along a small spectrum of representative democratic governance, and mixed-capitalist economies.
It is that second part that seems to attract much of the rancor.
Without getting into definitions of capitalism, the actual feature of the current economic system that elicits strong emotions is the ability of some people to acquire more wealth than others, and the consequences that result when this happens. Inequality of wealth distribution, however, is not a feature exclusive to capitalism, and this myopic view of the causes of inequality dooms proposals for revolutionary alternatives by failing to identify root causes, and thereby not effectively addressing solutions to the problem.
"A man does not know his own ADDRESS (in time) until he knows where his time and milieu stand in relation to other times and conditions" –Ezra Pound
Humans acquire wealth because they can. Any proposed system that seeks to upend this cultural trajectory cannot do so based on assumptions inherent human behavior that is not supported by evidence. The idea that by simply removing government individuals gain the power to treat with one another on fair terms ignores the fact that government was originally not something imposed from above, but willed into existence by people themselves.
The root of this situation is the emergence of one particular cultural trajectory that gained dominance across most of the world. It began over 11,000 years ago when ancient humans make the transition from nomadic to sedentary societies.
Once members of a society have acquired a level of material wealth they now have an interest in ensuring that their wealth is protected from being acquired by others. This can mean laws or arbitration to deal with simple theft, or more complex social systems where inheritance rights are introduced. Societies as a whole may now choose to take steps ensure that their communities are protected from the deprivations of others through such steps as building wall or other simple fortifications, or the raising of military.
This gives rise to a class of people who are given the right to enforce, arbitrate, and/or legislate new laws, and to the rise of the concept of positional authority quite different from that which can be demonstrated through efficacy in the hunt or on the field of battle. A situation where the individual, out of self-interest, has voluntarily surrendered a degree of will to a governing body, and the beginning of possible oppression* through non-physical means.
As populations grow, government is magnified, and the individual diminishes. Here we now are.
I do not believe, nor do I hear, calling for a return to nomadic societies is the answer to bringing greater balance to societies. What I do believe is required is an alternative system that takes into account the tendency of people to want to acquire wealth, and the need for mechanisms for personal and group protection. Until an answer for this is found all your ‘-isms’ will fail.
*Oppression through religious or spiritual belief systems is ignored here, although it is also important contributing factor in some cultural trajectory, and undoubtedly an area suitable for intense discussion.