Yeager wasn't that much of a national hero in the early 70's. As the book & movie The Right Stuff illustrates quite nicely, Yeager wasn't an astronaut, which meant he didn't matter. If you were a pilot and not an astronaut the John Q. Public didn't know you from Adam. The NASA media machine made it really clear that ALL the best American military pilots were in the program (which was, of course, a load of crap, but perception IS reality). His reputation in the flying community was that of a living legend, but that community was a pretty closed off one during the 'Nam.
Of course, the same book & film that showed why Yeager was forgotten was why he was later remembered.
So, to answer the question, nothing much happens.