> reboot their hardware project
This could go way beyond any potential hardware project, depending on whats actually true from the allegations and how much of Apple's trade secrets have been used or shared within OpenAI.
There were rumors a while back of OpenAI building some integrations into macOS akin to the Shortcuts app, and who knows what other computer use type projects. They could very well have been using information from within Apple for that.
It's kind of a fruit of a poisonous tree problem. If OpenAI used any of Apple's secrets broadly, Apple could ask the court for an injunction to block the deployment of any software from OpenAI. If discovery proves the IP contamination spread into other areas within OpenAI, it could completely freeze all of their deployments.
If Apple actually has the receipts here they could realistically bring down OpenAI entirely.