Actually it was boeing that called for the standardization for long range routes, as the correctly realized that most diversions have nothing to do with engine failures, as you just pointed out in your posts. Boeing wants the standardization because basically the south american market would need better that 240 minute etops on their routes and that is why the 340 sells down there, while the 777 kicks its but everywhere else.
Incidentally, both cases were poor planning on the part of the crew, partially because of a lack of information available to the crew at the time. At AA our diversion guide specifically lists how far away medical help is from the airport. ON the North Atlantic for example departing the flight plan to your enroute alternate of Keflavek would make almost no sense in the case of a heart attack because the hospital is 45 minutes away once you get the aircraft on the ground, where if you fly another 30 minutes and go to Shannon, the Hospital is much closer. (I know this doesn't apply for all tracks and all locations but you get the drift)
Also, once an emergency happens (lets say engine failure) the captain has extremely broad discressionary powers under his emergency authority to go any place he pleases with the aircraft. I myself am NOT going to shoot an engine out ILS to a windswept ICY 6500 foot runway when 30 minutes in another direction might take me to a severe clear warm and sunny beach with a 12000 foot runway. (Assuming of course I got the gas for it).
One thing to remember. I actually believe ETOPS aircraft are more safe than 3 and 4 engine aircraft as long as the crew excersized good judgement. Only ETOPS aircraft are required to have cargo fire fighting for the entire ETOPS portion of the trip. the 3 and 4 engine aircraft have no such requirement, and a cargo fire has lead to the loss of many large jets over the ocean while an engine failure has never lead to the loss of an etops jet over the ocean (or any that I know of since the jet age).
Cheers
Wino