Stephanie Sterling of the Jimquisition outlines the thinking involved here. Well, she swears at everyone involved for twenty minutes. So, Steph.
She seems to think the AI generates .WAD files.
I guess they fell victim to one of the classic blunders: never assume that it can't be that stupid, and someone must be explaining it wrong.
This is conceptually different, it just generates a few seconds of doomlike video that you can slightly influence by sending inputs, and pretends that In The Future™ entire games could be generated from scratch and playable on Sufficiently Advanced™ autocomplete machines.