It's mindless in that it doesn't actually point out any specific obstacle. It's just "it hasn't been done yet", as if that means that it can't be done. This is especially annoying when large numbers of people have been looking at the issue and have concluded that there is no such obstacle that would prevent it from scaling out.

And no, the technologies do exist. There is nothing new that has to be invented. They need to be run down their experience curves, but aside from that maturation everything is there.