Only the tech priests know the right incantations and rituals to commune with the holy machine spirit.

Literally any familiarity with the lore and it just makes sense, the kind of people the 40k lore would resonate with are unlikely to be AI chuds in the first place.

Though then again people do usually look way past any/all subtlety that might once have been intended and any franchise-ification of something usually destroys the remaining of originality as it becomes a facsimile of its original self.

But GW do seem to take reasonably good care of their IP and world, so I respect them for resisting the imminent slop-ification at least a little bit, there's enough shitty 40k work out there in both book and videogame form already. I'm sure the Abominable Intelligence will come for them eventually too, but until then, the emperor protects.

For who, Roboute Guilliman be using the Cawl Inferior like chatGPT.

I trust Data more than Lore.