Selecting a metaphor implies that ones imagination is - at least partially - constrained by the metaphor. AI as a powerpoint would make using AI for anything other than presentations seem unusual since that what powerpoint is used for.
Also when the original author "models as computers" what does "computer" represent? A mainframe computer the size of small apartment, a smartphone, a laptop, turing machine or some collection of server racks. Even the term "computer" is broad enough to include many forms of interaction. I interact with my smartphone visually while with my server rack textually, yet both are computers.
At least initially, AI seems to be something completely different, almost god-like in its ability to provide us with insightful answers and creative suggestions. God-like meaning that judged from the outside, AI has the ability to provide comforting support in times of need, which is one characteristic of a god-like entity.
Powerpoint wasn't built to be a god-like provider of answers to the most important questions. It would indeed be a surprising if a PP presentation made the same impact as religious scriptures - to thousands/millions of people, not referring to individual experiences.