My gut says that one could probably get there with ASObjC, developer.apple.com, a lot of time, and a case or two of Scotch. I'll pass on buying that ticket!
I play with scripting the UI when I have to. But there's something about writing code with 47 levels of item 1 of position of text area 4 of UI element 2 of row 7 of table 3 of splitter group 3 of splitter group 2 of group 1 of sheet 2 of...., knowing that with the next update of the app it's all going to change...
Anyway, yes, Apple could make this all much easier if they wanted to. It's actually kind of remarkable that this level of automation is possible at all. My understanding is that when OSX was released they came very close to shipping without a Terminal app. Thanks to the screams from Linux users. The idea of automation had to fight strong headwinds. We owe people like Sal Soghoian a huge debt of gratitude.
Then along comes Keyboard Maestro, handing out copies of the keys to the kingdom. There will always be things to grumble about, but this world is very, very much better than it might have been.