Which goes beyond a civil lawsuit as well, if true, these employees are going to face real, serious criminal charges and possibly jail time. Up to 10 years in federal prison, and Apple has a history of pressing criminal charges.
If Liu actually did exploit a vulnerability to bypass Apple's network security, they may also see federal charges for CFAA as well.
You can steal trade secrets, which is what this case is about.
(If you’re going to suggest a full rewrite of IP and anti-trust law, you should at least have an understanding of the current situation.)