Earlier quoted context omitted.
> And I disagree with this assertion. Heavily. Simply look at the state of most bridges in the US (and elsewhere?) to see that they are not holding up nearly as well as is implied by this assertion. I find that they (from the '50s and even older) hold up just fine. If software worked initially, and survived 60 years that well as bridges from the 50s do today, that would be a miracle.
This leads to a few questions, though. First, if bridges were built just fine in the 50s, why do they build them differently nowdays? Second, why is the maintenance cost of bridges decidedly non-trivial? Third, is there any software that is that old that still works fine? For the first question, I would only be offering speculation. Google and friends can give pretty good references. For the second, a quick google gi…
Onto bridges, just because they build them differently now does not negate the fact that 50 year old bridges are still reliable and safe to drive over because they were engineered well. Their shortcomings and failure modes are well known so maintenance can be performed to prevent collapses.
50 year old bridges may be expensive to maintain at this point, but the fact that it's still possible shows that they were engineered well. They may build them differently today, but that's more likely related to cost constraints changing (e.g. can't afford an army of riviters now) rather than the engineering being unsound.