Degrowth and "Maybe this uses too much electricity" are not the same thing, particularly when a nontrivial portion of US generation is fossil-fuel based.
As for the breakthroughs, maybe they will, maybe they won't; it's not much of an argument.
endless growth is the philosophy of an economic system that does not regard the long-term health of the planet and its flora and fauna. what's your point?
Maybe LLMs will help lead to a breakthrough in nuclear fusion or battery research.
Degrowth is the philosophy of poverty, and a poverty of philosophy.