the reason for the lack of interest in the 744 is the same as what happened on the Atlantic several decades ago when it got replaced by smaller twins.
At one time, traffic flowed from a few hubs in the US to a few hubs in Europe. With the arrival of the 767, it became possible for carriers to open multiple gateways in the US to places in Europe that had little if any nonstop service - routes such as ATL to Stuttgart.
NRT existed as a hub because the Pacific was concentrated in the hands of DL and UA from the US carrier perspective.
NW had little choice but to continue to rely on NRT because it didn't have the presence outside of the Midwest to have service to most of Asia - and there were few planes that could fly to multiple points in Asia from the Midwest.
NW was counting on the 787 but it was delayed and then they got bought by DL who built up DTW to Asia using the 77, the first non-747 that could really develop Asia.
UA has been flying the Pacific extensively as a result of the Pan Am acquisition and focused first on developing SFO to Asia and later ORD. Other gateways such as EWR came with the CO acquisition.
UA has been able to diversify away from NRT because of its stronger west coast presence and its ability to use 744s on routes into China and HKG based on the amount of demand.
As the Pacific continues to develop and historical strengths become less important, including AA's push into the region and the strength of foreign carriers outside of Japan, DL and UA have to shift their networks to smaller, more efficient aircraft and serve as many cities as possible from their strongest hubs in the US and not just the west coast or NRT.
The US carriers compete successfully to Europe based on using multiple US hubs and by serving smaller points in Europe which Euro carriers cannot serve as well because they don't have access to the strong hubs in the US - except as part of joint ventures.
The 787 and 350 will further fragment the Pacific and allow long, thin routes from many hubs.
DL is using current generation 767s and 330s to get what it can with minimal aircraft investment, similar to what CO and TW did with the 757s from NYC to Europe.
The 744s are just too big to compete in a fragmenting market.
As to uses on the Atlantic, it is possible. DL runs multiple 333s or 777s (just under 300 seats) from DTW to AMS so the 744 is not a big step up in capacity.
DL also tried to bring the 744 to GRU but the Brazilian aviation authority did not want any more large aircraft until the newest terminal is open and some carriers change terminals.
DL since has received a 2nd ATL-GRU flight so I'm not sure the 744 will come to GRU even though multiple airlines have moved or will move out of the current terminals to the new terminal.
frequency counts as much or more than adding bigger aircraft from the perspective of US carriers.
Foreign carriers have one or two major hubs at most. US carriers have multiple hubs. They get higher revenues by having multiple smaller flights per day from multiple hubs than Euro carriers get with one or two 744s or A380s from many foreign cities to their hubs.
