This is a bet that's as insane as the Apple car. They're going to try to get people to buy a specialized device from a company that isn't just a software company but really a B2B API company—the only successful consumer-facing product they have ever released was an accident, a tech demo that went viral.
And what exactly is that device going to do that the iPhone (and smartphones in general) can't already do with at a minimum a few small tweaks to the existing flagships?
In the right context vertical integration can make sense, but hardware is a big stretch for OpenAI right now. They haven't even really pinned down the consumer software angle yet.