He's mentioned in the third paragraph of the link. But yes, it is. In order for it to be "worth" burning a trillion dollars every year on AI, then there has to be a time in the near future, 2030 or so, where AI will be making unimaginable trillions. If the datacentres aren't being built, then that money can't possibly be coming in as planned. That makes the massive investment in NVidia's GPUs look extremely shaky - why buy them if they'll never be turned on? - and it means Oracle will be completely in the shit.
Ed's arguments have been, "if any link in the chain fails, the whole thing falls down". I think he'd been leaning towards "banks being unwilling to keep financing datacentre builds on debt" as the most likely stumbling block, but just being unable to power the damned things for want of infrastructure and skilled engineering, as here, is a problem he talks about frequently too.
He thinks it's likely it'll bring down the entire tech industry, since they're now full of idiotic MBAs with no other big ideas. And frankly, it's about time.
I'm all here for the green energy. I think it's worth investing in "both sides of the coin", though. Now that I've replaced all the energy-wasting bulbs in the house with LEDs, and the house is well-insulated enough that there's just no need to run a three-bar electric fire to keep warm, then I'm at the point where solar panels would be sufficient for nearly all my energy requirements. That's partly because solar has got better, but mainly because I'm just using loads less
On that note, the secret to not having power and cooling issues running tens of thousands of super-hot GPUs in the desert, is not to build them. Which as they're not being built, might be enough ;-) But investing in more effort processing units and more efficient models would do it too. They wouldn't have their "no one else can afford this" moat if it was all made more affordable, tho.