I revisited Emma Goldman's essay "Jealousy: Causes and a Possible Cure" because of this question.
I believe any conflation of "relationship anarchy" and polyamory is reactionary - “manifesto” or no. I will only speak of Euro/Western traditions, but monogamy has been so long and violently policed by church and state that a freedom [from] conservative coupling might make one interpret multiple lovers as anarchistic in itself. Similarly, a more communistic escape route from this same authoritarian conservatism might find one advocating for a communisation of the means of production. (All puns amusing).
Now I’m thinking of another essay: Aviv Etrebilal’s “Butterflies, polyamory and ideology: Letter on inconsequence.”
The essay speaks to this same reactionary escape from Old Regime and Modern conservative sexual ethos and how, over decades post the “Sexual Revolution,” polyamoric behaviors can become dogmatic, moralized norms. (I will reiterate that this is a socially-enforced coercion of one’s sexual / intimate behaviors found like that found in monogamous conservatism. Not exactly anarchistic).
I am not “against” group sex or of having plural orafice engaged simultaneously by (at minimum) two individuals at the same time or whatever agreement might occur in which individuals are not monogamous. Honestly, I am no sexual-scientists and find many categorically “relational” behaviors.…I don’t know….Interpret the features of others’ [sexual / romantic / intimate / whatever] how you will.
(As an aside: there are not enough anarchistic English words to communicate anarchistic thinking. I’m not utopian about language, but I will say that these are some dang squeaky wheels).
I’ve written a lot and said little. The basic points that I want to make are
anarchistic relationships are separate from maintaining multiple, sexualized relationships simultaneously. That polyamory, if interpreted as necessarily anarchistic, is false. (Or “relationship anarchy” is dogmatic if interpreted as polyamory. Either way).
Giving preference to a particular relationship over another relationship is not hierarchical. I will not feel obliged to treat my friends and Cutie-McBooties like units traveling along a factory line or like electronic devices that I must systematically plug into the grid to recharge. If I may be allowed my pulpit, treat individuals like individuals.
On the preference of which relationships to "spend" time or attention: This preference would only be hierarchical if an individual was sorting lovers and friends like a king might favor grueling lords. Within polyamory, it is not anarchistic to center social-gravity by deciding which sweetheart will receive more social power than the “runner-up” lover. (If you feel that a lover is manipulating your scene or friendship group in such a way, I might advise some revolt. This is not necessarily aggressive and hateful. See a recent question on BDSM for creative, loving approaches to kicking a lover’s ass. Just kidding, that question needs lube. BDSM jokes are fun, but, in all seriousness, this dynamic is a very unsexy red flag of power-abuse).
Anarchistic relationships are not positions or roles for one to fill. They are not performances with a script. They do not come with preordained timelines, social expectations, coercion, possessiveness / commodification, or whatever schema upon one might press.