Yes. They argue Helion screwed up computing the rate of energy flow from fast ions to cool electrons. I have not seen a good rejoinder from Helion, which is a very bad sign.
Given this, and given the apparent failure of Zap's scheme to scale, I don't think fusion has any significant chance of succeeding now.
Given this, and given the apparent failure of Zap's scheme to scale, I don't think fusion has any significant chance of succeeding now.