Can't speak for Rob Pile but my guess would be, yeah, it might seem hypocritical but it's a combination of seeing the slow decay of the open culture they once imagined culminating into this absolute shirking of responsibility while simultaneously exploiting labour, by those claiming to represent the culture, alongwith the retrospective tinge of guilt for having enabled it, that drrove this rant.
Furthermore, w.r.t the points you raised - it's a matter of scale and utility. Compared to everything that has come before, GenAI is spectacularly inefficient in terms of utility per unit of compute (however you might want to define these). There hasn't been a tangible nett good for society that has come from it and I doubt there would be. The egarness and will to throw money and resources at this surpasses the crypto mania which was just as worthless.
Even if you consider Rob a hypocrite , he isn't alone in his frustration and anger at the degradation of the promise of Open Culture.
"There hasn't been a tangible nett good for society that has come from it and I doubt there would be"
People being more productive with writing code, making music or writing documents fpr whatever is not a improvement for them and therefore for society?
Or do you claim that is all imaginary?
Or negated by the energy cost?