A case like this leaves institutional scar tissue. There will be new sections in HR policy manuals and training programs. Executives will be gun-shy about any conversations that even come close to those at the heart of this lawsuit. There will definitely be an effect.

For a while. As time passes and this case fades from memory I expect such collusion to eventually happen again.

That's the nature of all crime.

Unless you're an idiot you either stop doing it, or get better at it. That's why when you commit a crime they send you to criminal school, so you can swap notes about all the other ways guys got caught.