Maybe not a "red flag" but I wouldn't be desperate to hire anyone with no experience, even in the Silicon Valley where competition for engineers is fierce. A headcount is a headcount as far as investors are concerned, so I'd rather have someone with more experience that also costs more.

Even still, I agree with the parent up above. A degree isn't strictly necessary, and if someone had the motivation, the talent, and the cert, I'd be willing to give them a chance as an intern.