Which, I ask you, was the more successful containment?
The requirement and design intent for containment is not a 100% requirement which of course is impossible to acheive so it's not even attempted.
Instead the regulations look at it as similar to many other requirements including birds, ice etc. The regulations set forth a minimun level that must be demonstrated by test and analysis.
For engine containment the demonstration requirement is for the more likely failure of a blade and its consequences at maximum running speed. Given that in the QF 32 event a disk separation occured t would have been impractical for any engine design currently existing to have contained the debris by verifieable design.
Instead the burden falls to the design intent to minimize the failure condition that caused the non-containment using best industry practices. This does include but is not limited to the presumption that some designs will permit the blades to be mangled in order to save the disk.
Indeed there was a lesson learned in all this for all manufacturers not just RR