While I think the article has the time-line and focus correct, it kind of glances over the fact that Solarpunk is one if not the only -punk suffix genres that can claim some legacy in the actual (anarchistic) punk movement, albeight or maybe especially because it does not really attempt to mimic the astethics of it.
Steampunk doesn’t even pretend this, and Cyberpunk was rather modeled on the astethics of 1980ties street-punks as seen by non-involved middle class sci-fi authors. I think only cypherpunks can somewhat claim an similar legacy of thought as Solarpunk can.