That was FaceTime that they intended to open source, and it was supposedly a patent troll that forced them to move FaceTime to a more centralized design (it was originally P2P) which in turn made open sourcing more problematic.
That was certainly the excuse. But it is trivial for Apple to buy any patent it needs. I believe the real reason is that FaceTime and iMessage hook people to Apple platform and discourage switching to another one.
The patent troll in the case got a 440M award… and Apple had to spend a bunch of engineering time throwing out the already-working p2p implementation and rebuilding a centralized version… and you’re suggesting that this was all a mere smoke screen?