I am not rejecting the sensibility or agreeability of the principle on its merits as a moral principle, but I do reject your characterization of any representation of responsibility as being a “descriptive fact”.
I feel, unfortunately, that such conflations represent a thematic flaw latent throughout the argument.
Simply because we approve of particular facets of social relationship and social structure, we may not assert them as facts, transcending our preferences, whether individual or shared, except as that they are facts of our preferences.
Anarchists seek to replace the state with systems that are constructed through full participation, not to reproduce the state with a different one that may seem to some as more appealing.
Would you mind explaining your understanding over the incompatibility between consensus and mutual aid, and what you imagine may be neither coercive or consensual?