I think they're pretty different cases.
Amazon's one was essentially a side project for them, likely fully funded in-house using their R&D (research and development) budget.
In Nate's case, it was their entire product. They received funding from investors purely for the AI functionality that didn't actually exist or work. They specifically claimed that it did work, which is how they got the money. They spent all the investor money and had essentially nothing to show for it.
Just some parts of it. https://github.com/bluesky-social/pds