What do you mean “no one would want stock android”?

That’s the whole selling point of the Pixel serie phones. No 3rd party bloat or unwanted features, quick updates, etc.

Back then OpenAI also heavily used/developed/showcased the AI technology for DOTA 2 (Valve’s game) bots, at level which was spectacular at the time. It makes only sense that the front face of a company shows interest in the (non-profit at the time) product of their partner organisation.