Because Johnathan Blow programs in Jai and his experience is talking about the tradeoff set with <technique X> when using Jai.
Since we plebians can't use Jai, that tradeoff is irrelevant.
For example, Jai has hot loading, IIRC (somebody please correct me if I'm wrong). The utility of an embedded scripting language is completely different if your tooling has really good support for hot loading of your engine implementation language.
Furthermore, because we plebians can't use Jai, we can't verify anything said about it in context, either.
Since we plebians can't use Jai, that tradeoff is irrelevant.
For example, Jai has hot loading, IIRC (somebody please correct me if I'm wrong). The utility of an embedded scripting language is completely different if your tooling has really good support for hot loading of your engine implementation language.
Furthermore, because we plebians can't use Jai, we can't verify anything said about it in context, either.