Re: Exactly this...
《Earlier space efforts were built on rigor, lengthy and specific and detailed checklists that were themselves built on checklists, and everyone involved was focused on getting as close to perfection as humanly possible.》
This was brought home to me years ago when visiting the "Powerhouse Museum" in Sydney where there was some Gemini hardware on display that a visitor could inspect closely.
I was really surprised at the precision and fineness of the workmanship. There were wired seals everywhere which presumably denoted completion and provenance.
A different culture and attitude.
Another thing I noticed at the time was that much of what I could see wasn't all that complicated. So perhaps St Exupery's aphorism from Terre des Hommes (Wind, Sand and Stars):
《 Il semble que la perfection soit atteinte non quand il n'y a plus rien à ajouter, mais quand il n'y a plus rien à retrancher》
was implicitly understood by those engineers, scientists and technicians.