ETOPS was perused by both Boeing and Scarebus so they could sell big twins to airlines to operate the Atlantic and Pacific more economically, with the comparable safety to the quads they replaced.
Now, that Twins flying ULR is the norm, it would seem that some want to limit the Quad operation to that of the twin.
A quad continuing on three suffers another engine failure. It now drifts down and diverts to a planned enroute ALTN, exactly the same as any Twin would do after a single engine failure.
A twin on a 207min ETOPS flight over the pole suffers an engine failure. It now drifts down and all on board wish they were flying in a quad.