BS.
We're still exploring the space, and most of the time the things we build are good enough to work - just like the first wooden planks across streams were good enough.
We also do have the capability of designing and building the software equivalent of suspension bridges across the bay, using tools and processes like Ada, Coq, formal software proofs, etc.
Most engineering projects don't live up to your high standards, either. I knew a Blacksmith who would make circular staircases, and would regularly have to work around floors which were 4-6" higher or lower than specced. Or bridges which were put into earthquake zones, but not designed to withstand earthquakes. Or highways built with inappropriate foundations that buck like a bronco with frost heaves after the first winter passes. Or cities built under the freaking water table.
Ease up here folks. Our tooling and processes are still undergoing growth, as we take in the incredible scope of what we are capable of. Rome wasn't built in a day, and the understanding of stoneworking, woodworking, and city planning which enabled the building of Rome certainly took more than the < 100 years we've had.