As in, a claim that it is physically impossible to build more housing than we do. So if you raise costs and restrict methods, that won’t reduce supply.
It simply is not possible to interpret the thing you quoted as saying this. He mentions permits explicitly as one of the limiting factors!
Update: after having interacted with Fable 5 during the brief time that it was available to me, I think multiple intellegences models are simply true. I expect LLMs to get better, perhaps even by significant amounts, but I do not expect step-changes in capabilities and I do not expect general superintelligence from existing research and product paradigms. I also expect that AI economic contribution currently has a lot of overhang, in that strong models should drastically improve productivity in certain fields, but the workflow to do this without accumulating debt in LLM blindspots is not known.