This article at the Financial Review, and not behind a paywall, describes the issues in the case and argues the settlement definitely was a capitulation by Porter.
I would also comment that the world of defamation lawyers seems particularly incestuous, even taking into account that the world of barristers and judges is routinely kinda incestuous.
I think that everyone now is curious about the additional redacted evidence that Porter wanted to keep out of the trial. Particularly from the guy who said he had a relevant conversation with Porter about his time with the deceased.