Nah, it peaked with Supremacy.

You could consider Supremacy and Ultimatum to be co-depedenant, but ultimately from Ultimatum onwards, they do the same thing.

"Oh actually, THIS GUY was the one who was there from the very beginning and is the real mastermind behind Treadstone."

"Wait, actually, there's ANOTHER secret about how you become Jason Bourne at the very beginning."

I stopped caring the moment I noticed the pattern.