Did they do meth/heroin type of stuff, have tumultuous personal life, or professionally they didn't achieve much after being astronauts ?
Just because we haven't fully achieved the potential of sending humans to space yet doesn't make it less of an achievement. Perhaps when we finally colonize space we'll appreciate how pioneering the Apollo program really was, especially as we forced it all through before we were even really ready, technologically.
Space exploration is meaningful when the first person is born, grows up, and has a kid on some other celestial body. Whoever that is will be a milestone worth remembering, until that point it’s just flags and video.
Let alone all exploration that doesn't result in immediate colonization?
To come back to my point, the astronauts were singled out and idolized and that didn't have a bearing on reality. If today someone were to muster modern science into an astounding vehicle of marvelous engineering and ambition, and it would require a human technician to operate, and let's say I would be that technician, you wouldn't say that I'm a hero or a person of extreme merit, because I would be just a technician.
Enter framing. If I would operate the device or vehicle on some interesting journey, and I would then go off to shake hands with some politicians, and there was some incentive for the media apparatus to spin this in some simplistic, easily graspable way, they would have everything they needed, and I'd become a vivid symbol of that marvelous flowering of our civilization (or of US, given the Cold War context).
Will you ask the casual observer to grasp the grandiose complexity of what led to this event, or will you just give him a pawn-head in the form of an astronaut and say "idolize him", thus letting him confuse a flashy front-man for the real thing?