> She was likely very strongly pressured to sign it with various threats and consequences if she didn't.

Like what? If it's something you sign when you leave, it generally comes down to whether you want some level of severance payments/accelerated vesting or not, even when you're fired (when you're at the executive level).

Basically, the company says: if you agree not to sue us or disparage us, here's a bunch of money.

There are no threats. The consequence is, if you don't sign, you don't get the extra money. It's completely and entirely voluntary.

She was a highly paid executive who chose to get even more money in exchange for keeping her mouth shut. Now I think it's great she wrote the book, I love transparency. But nobody can be surprised Facebook is taking legal action when she presumably took their money under an agreement not to disparage. Nobody made her take the extra money.

Remember this next time you have cancer and get fired, and then have the option to “voluntarily” sign something to keep receiving money until hopefully you’re well enough to look for a new job.