People died going to the moon the first time. Better to not go at all, or to have it cost 10x as much, than to risk even one astronaut's life. Besides, if we j

People died going to the moon the first time. Better to not go at all, or to have it cost 10x as much, than to risk even one astronaut's life. Besides, if we just redid what we had, we would not be developing any new tech that could be used on earth. And it would be less comfortable, a very bad thing if you're still fighting the losing battle to convince anyone that they'd like to be in space for more that a brief adventure. AFAIK they have cuirass ventilation to replace iron lungs now. Those new tractors are most likely way more reliable. In practice they may be worse because of artificial limitations put there on purpose, but were it not for those it would almost certainly be better(Although people would probably still like the same ones, because no matter how reliable something is, people seem to like things with a "substantial" feel that they can understand).