I can't claim to be a libertarian, but I don't think minarchists claim to espouse an economic system at all. You may be thinking of left market anarchists. And I'm pretty sure some libertarians will make their point with private force applied to consenting market participants used to secure their capital markets.
Also this isn't meant to be an exercise in ideological critique so there's no need to defend what "many anarchists" think. My post was just there to demonstrate how many strains of anarchism there are and how few goals they tend to share. Also it's partly to remind folks that there are more than just Ancoms and Ansocs out there, even if they tend to be the most vocal in tech spaces.
My reply was a little ambiguous - I simply meant that many anarchists would find the minarchist and libertarian positions you lay out to be self-contradictory. Namely, they both claim to (mostly) oppose state involvement in the economy, yet (generally) support a free market economy that needs to be enforced by the state.
I'm agreeing with your premise that anarchism consists of many competing strains, just adding a point of clarification for the audience here (...which is probably more familiar with the libertarian perspective than the others you listed).
Also this isn't meant to be an exercise in ideological critique so there's no need to defend what "many anarchists" think. My post was just there to demonstrate how many strains of anarchism there are and how few goals they tend to share. Also it's partly to remind folks that there are more than just Ancoms and Ansocs out there, even if they tend to be the most vocal in tech spaces.