Agree 100% -- I couldn't have said it better! In my professional life, I have often met consultant types with super vague technical ideas that (surprise!) they were secretly working on implementing. They woudn't release anything because they fear being criticized. The GUI was a big deal and still is to this day. Xerox PARC did change the world. Ted Nelson? Not so much...
Old man, bitter that Alan Key, Steve Jobs & Xerox PARC got more money & credit than he ever did. Who the hell cares about his gripes? The "legendary story" was generally corroborated by all parties involved.
Ted Nelson has yet to admit missing the boat by never being able to release anything in over 40 years. He is a super-consultant & inverse opposite of what Y&C stands for. A great visionary with zero implementation skill. Time to die.