A few thoughts here. I want to emphasize that I'm intentionally stepping back from taking a "side" - if one can be taken in this context.
I think there's a real question here about what the left is that needs to be answered before we can figure out whether or not primitivism is part of it. Palmares response touched on it in a really useful way by pointing to the idea of a "post-left". So, is the left:
a) A historical "movement" and set of discourses - a lineage that can be traced more-or-less to the enlightenment and Republicanism? To what degree do other ideas that have engaged to varying degrees with "the left" become part of it? e.g. Are radical Indigenist ideas "left"? Was Max Schatman still left after he swung right? Etc. Depending on where one draws the line at which one "breaks" with the left, primitivism (and post-left currents generally) could certainly be understood as left.
b) Fidelity to radical egalitarianism? Primitivism probably counts as "left" on that basis, as do various millenarian religious movements, etc.
c) Fidelity to progress? i.e. Is the left rooted a particular notion of history as a movement from "necessity to freedom"? That is, is the left the bastard child of European liberalism? In this last case, Primitivism (and most of the post-left, various radical religious movements, various Indigenist movements, etc.) would not be left.
d) Is it some combination of these things? In what proportions or on what terms?
As an aside, I think "primitivist" is largely a term that has fallen into disfavour, since it projects a problematic and distinctly civilized dichotomy into the discussion - reflecting, I think, the heavy influence of academic anthropology on some iterations of primitivist thought. "Anti-Civ[ilization]" is more common now, and also represents a broadening of discussion which, while acknowledging certain aspects of "primitivist" critique, is something less than a wholesale swallowing of Zerzan.
For an interesting aside, I highly recommend reading Camatte's The Wandering of Humanity - a distinctly Marxian work which some view as an important influence on what became "primitivism". Similarly, the latter work of Fredy Perlman falls into this category. I highly recommend his extremely poetic Against His-Story! Against Leviathan! for anyone who is interested in an attempt at a post-Marxist materialist critique that represents an important early document of "anti-civ" anarchism.
I personally wouldn't connect primitivism with the left. Of course I'm ok with this as I am particularly bothered by the left.
Out of curiosity, what are your thoughts on anti-civ thought? (Sorry if you posted them and I just didn't notice)
"I'm not interested in indulging whims from members of your faction."
Seeing as this is seen as acceptable by an admin, from here on out when I have a disagreement with someone I will be asking them to reference this. If you want an explanation of my views, too bad.