For a few decades in the middle of the last century, American cities tore themselves down on purpose. Urban renewal demolition cleared whole districts of older buildings for highways, towers, and plans that looked bold on paper. It was demolition at a scale the country had never tried, and it decided in bulk which building stock would reach our time.
For salvage the wave cut two ways. It released a flood of old material at once, mantels and doors and hardware and fixtures and glass, all coming out of buildings in the same handful of years. Some got saved; a share of the good salvage still in circulation traces to this period. But the speed and scale meant most of it was destroyed outright. Clear a district in months and nobody is carefully pulling sockets or wrapping shades. The machine doesn't sort.
What survived skewed toward the exceptional: the building someone fought for, the fixture a salvager reached first, the material valuable enough to justify slowing down. The ordinary fixtures in ordinary rooms mostly went to landfill. So the salvage left from this era leans grand and misses common, which distorts how the period looks to anyone reading it through a yard today.
Urban renewal was not only a loss of buildings, and the buildings are the least of it. It cleared houses, blocks, shops, churches, and streets people used every day, and that cost outweighs any question of fixtures. But even confined to the material, the pattern holds: fast, total demolition saves almost nothing, and what it does save survives more by accident than intent.
A piece that came through those years got there because one person, at one site, decided to save it while everything around it went down.