“CTO” makes sense as a signal that “the buck stops here” for technical issues. They are the highest-ranking authority on technical decisions for their silo, with no one above them (but two CEO’s above them for business decisions)

If Mira Murati (CTO of OpenAI) has authority over their technical decisions, then it’s an odd title. If I was talking with a CTO, I wouldn't expect another CTO to outrank or be able to overrule them.

It would be quite strange indeed for Mira Murati to have a say over their technical decisions, considering she does not work for OpenAI :)