Patrick Collison
I think the pity and mockery stems from so many Europeans (usually institutions/"experts") dismissing AC's utility. The vast majority of the debate is not over the mechanics and logistics of deployment, but whether widespread AC is in principle desirable in the first place. I think it garners so much attention from Americans (and Europeans such as myself) because it's a vivid distillation of the self-destructive "degrowth" hysteria that is so prevalent and harmful in many European policy matters. It is the same impulse that led to Germany decommissioning its nuclear capacity, and it is a substantial contributor to the broader economic challenges of the continent.