Your argument is that because FOSS would be permissible in AnCap society…
Because voluntary association and sharing is also a core tenet of volunteerism/anarchocapitalism, as they also are of anarcho-communism…
FOSS being fundamentally constructed upon AnCom principles of rejecting Capitalism and centralization in favor of decentralized and collectively owned and distributed property
FOSS being similar to AnCom because both share principles of sharing
makes it not in line with Anarcho-Communism.
makes it notnecessarily Anarcho-Communist.
You’re making false equivalencies for the sake of it.