In the 2008 Net Aesthetics panel at the New Museum no one used the term "post-internet" (with or without hyphen). So it's amusing that in this year's so-called Post Net Aesthetics panel (which, according to Rhizome, "picks up the discussion from [its] Net Aesthetics panels of 2006 and 2008," the subject was whether the term "post-internet" had outlived its usefulness.
With all deference to Gene McHugh, who called his blog "Post Internet," the term was laughable if you ever said it aloud outside a group of seven or so recent graduates of the School of the Art Institute of Chicago (one of whom co-organized "Post Net Aesthetics"). Any use of "post-" 100 years after post-impressionism is inherently pompous, and since no "internet artist" was actually leaving the internet, it never made a bit of sense except to this SAIC-based group, who used it repeatedly and reverently (but always with a bit of "yet, is it over?").
Presumably they used "post-" in the art historical sense of "reacting to but incorporating elements of," but since "internet" isn't exactly a narrowly-defined style, it's wildly over-reaching to say you belong to a movement running counter to it. Especially since the only reaction anyone could see was the retro-direction of showing in galleries, or "material engagement" (hideous phrase), while the artist also maintained a net presence.
Thin gruel for a movement, or a panel topic.
Update: Dump chat on this general topic--
cdanger: post internet = non-screen media, gestural + spatial i/o and other sheeeit
tm: that sounds like "non-internet"
cdanger: "non-internet" [...] sounds like "internet of things" if we're going by terms other people made up
tm: "internet of things" sounds awful