There's already case law on these sorts of shenanigans: Midler v. Ford Motor Co., so Altman was either ignorant of this, in which case OpenAI needs new counsel, or he knew and did it anyway, because fuck you Scarlett Johannson. I'm pretty sure it's the latter.

https://gizmodo.com/openai-pausing-chatgpt-4o-scarlett-johansson-voice-1851488261

OpenAI Will Ditch ChatGPT's Scarlett Johansson-Like Voice: Report

ChatGPT-4o's "Sky" voice belongs to a different actress and is not meant to be an imitation, OpenAI said

Gizmodo
@scalzi So glad these amoral, arrogant techbros are in charge of developing technology that looks to insert itself deep into our lives. What could possibly go wrong with that?