Give it a chance. He comes at it showing sorta a worse case and then goes through how there are things that make it seem worse are actually not as bad. Nothing he goes through seems to be way off. So as far as I can tell its pretty even take. Not to rosy and not to doomy.
I think the IEA chart looks into where the energy began, not what it was used for. The 50% number rings true to me, at least for the heating in cold winters. As for summers, cooling is a heat issue as well, so that’s where much of the energy is spent.