A few comments - I won't bother quoting the exact posts since the mods have been removing much of the quoted posts.
ETOPS - part of the ETOPS equation is that most engine failures occur during takeoff or initial climb, not during the ETOPS portion of the flight. Failures - particularly catastrophic failures - are very rare at cruise. This is also true of FBO events. While a FBO can happen anytime, it's most likely to occur during takeoff or climb since that's when the fan blades experience the highest loads.
As I've posted previously, it was discovered during the 777 development program that some of the assumptions that had been used for FBO loads to the nacelle and engine structure were not valid - at least not for the (then) new generation of very large, very high bypass engines. As a result, higher FBO loads were used during for the 777 and subsequent programs. Recent experience suggests those loads need to be re-evaluated.
The PW4000/112" engine and the associated installation is out of production - and has been for about 15 years. That results in different treatment of things like these FBO events than would have resulted if it was still being produced (expanding fleet). Instead, analysis is done of the probability of a future, catastrophic event given the size of the existing fleet and how long it will remain in service. Hence, a relatively small fleet such as the PW4000/777 will be treated differently than a large fleet such as the 737NG/CFM56. No first hand experience (retired before the first PW4000/112" FBO event), but the process will look at the probability of a future PW4000/112" FBO event - presumably with some mitigation factor for more frequent, improved inspections - with additional probabilities assigned for the chances of a future event becoming catastrophic (remember, as dramatic as this event was, no one was hurt and the aircraft did not suffer serious damage - granted the next one may not be so lucky, there is a good chance it would). That process will determine what - if any - additional steps are required to maintain the expected level of safety. Now, before anyone starts in on their criticisms, know that while there are some Boeing specifics in the process that will be applied - the process itself is used throughout the industry, with a high level of FAA and other regulatory involvement.
Not privy to details, but the recent 777/PW4000 and 737NG events appear to share a common theme - fan debris is going forward of the containment ring and damaging the inlet/nacelle - leading to structural failure of the inlet and nacelle. This is something new - I don't recall that ever been seen before a few years ago. There had been cases where fan debris impacted the inlet forward of the containment ring, but it was low enough energy that it didn't do meaningful damage. For some reason that's changed (my guess is it's related to the higher bypass ratios of the newer engines, but that's just a guess). However I believe that's where the focus need to go, since I doubt any engine installation out there is going to deal gracefully with high energy debris impacting the inlet/nacelle forward of the engine containment ring - the inlet and nacelle are simply not designed for that.