I have spent time in Japan and assisted with international athletic events. Nagano Winter Olympics.
I say these things in defense of the Japanese, and from my personal experience in working with them. They can seem a little quirky at first, but once you understand it all, it makes total sense and you fully appreciate them, their efforts and love them for it.
Please understand that they are extremely detail oriented and want even the smallest little things to be as near perfect as possible. They have made an extremely detailed plan for exactly how everything will be, and if there were any questions they were addressed long ago.
They will leave no stone unturned to accomplish this. They will literally and figuratively go the extra mile to ensure everything is just so. Armies of people in Japan have been working on the 2020 Olympics. You likely can not imagine each and every thing that they have planned for.
They have a tremendous amount of national pride, and they view hosting the Olympics as much more than hosting an athletic competition. They have spent years planning these Games. They want to be the perfect host, and they want to host it their perfect way.
Please understand also how important the marathon is to the Japanese. You can bet that every Japanese marathoner who thought they might make the team has trained on the course. Brett Larner even mentioned seeing top runners on the course when he did his one year before test run. Imagine all the details Japan has planned and arranged to ensure their athletes, and what will likely be the marquee event at these games, will run as perfectly as possible.
( I predict at least 2 road medals for Japan in 2020...)
I can only imagine the disbelief and scrambling that is going on behind the scenes after being told at this late date that they will have to move the marathons and walks to another location.
It reflects poorly on the IOC to wait so long to do this. Telling your host what they must is just not something that you do.
Being told at this late date that they have to move the marathon likely seems outrageous and incomprehensible to the Japanese, on all levels (ethically, logistically, morally... ) What you are hearing is backlash, but many Japanese are too polite, too civil and too respectful to just tell the IOC what they really think.
The $US 300 mil figure is one way for them to express their extreme displeasure. Surely the IOC and others can understand money?
I have no doubt that Japan will be able to accomplish the venue change, but it will not be easy and it will come at a great costs.