> anti-poaching

The term make it sounds like a good thing, however I do not know if this was really a net positive. It might have helped the companies but isn't this anti-competitive at the employee level?

These companies (e.g., Intel, Google, etc.) also had to compensate their employees as a part of the settlement. Especially for people in engineering orgs, many of them received decent settlement checks.

And successfully at the time (illegally) squashed unionization efforts by software engineers

wasn't that just last decade?