The common answer is that it's survivor bias. Every once and a while I run across a home from the 1800s that probably shouldn't have survived, and the shortcut

The common answer is that it's survivor bias. Every once and a while I run across a home from the 1800s that probably shouldn't have survived, and the shortcuts the builders took are similar to today's shortcuts. Improperly sized beams, improperly spaced rafters, etc. In some ways, you could consider an 1800s rubble foundation and irregular framing spacing worse than today's shortcuts.