I understand the hard feelings old time ITF authorities would have, however, I truly believe it is time to get beyond all the bitterness and unite the art into a universally tightly governed, standardized, recognizable art, not ITF not WTF but the best of ea.
Personally, I dislike the idea of complete standardization. I think the creation of standard names for all the techniques in TKD by the ITF, and the naming of different judo techniques by the IJF is a great step forward, and very useful. However, a standard curriculum in my opinion is simply too restrictive on the individual needs and preferences of instructors and their pupils.
People are always going to have slightly different goals and preferences. Some instructors prefer to do a lot of pad work, some prefer to do lots of patterns, others do very little sparring. And that's fine, afterall, a martial art should not just be a fixed immovable thing, it should be flexible to the individual. An analogy is in modern schooling. Some people learn kinesthetically, some learn better from reading books, others from discussing the ideas. Schools in britain now try to cater for this, and results seem to be improving, so there is some evidence it works.
I have met instructors who were fantastic teachers at certain elements of TKD, but were weak in other areas, and obviously they focused more on the aspects they were good at than those they were poor at. That is not to say these weak areas should be ignored, but I can quite understand how some areas can be taught in much smaller amounts than others. A simple example is gun defense- might be a useful thing in America, but in Britain it becomes much less important, although knife defense might be more important. So you see how a standard, one size fits all, curriculum can actually stifle a MA and cause disagreements and splits where they needn't exist.
That is how TKD is now and there is much complaining and finger pointing. You raise some good points but no matter how you look at it we are still divided and many have hard feelings. TKD could be standardized if it was done correctly. You could do it regionally, that would take care of the gun SD in America vs. the knife SD in Europe example you gave. No matter how you develop curriculum instructors will always very a little from it but a minimum standard could be imposed and regulated. The curriculum would not have to be so rigid that it would impose on instructors, the key would be the minimum standards.