"it's being used as an AW/EP to make up for the lower levels of ZDDP in the GF-4 formulation" YUP. Chevron does use moly in it's Supreme and Havoline formulations. It's not the only path, but it is a good one.
Too bad the ZDDP was reduced to meet OEMs requirements. It worked well and was cheap. Still some in the oil, just less... They did not have conculsive data on caltalyst degredation, just some resonable judgements and fears due to LONG emission system warranties now required. Consumers pay indirectly for the new requlations as the costs went up to make the product for all suppliers.