The upholsterer proceeded to lecture me, in a helpful, passionate, and sometimes kindly manner, about how sofas made in the past 15 years or so are absolute garbage, constructed of sawdust compressed and bonded with cheap glue, simple brackets in place of proper joinery, substandard spring design, flimsy foam, and a lot of staples.

The big change in shipping logistics came when furniture manufacturers developed new ways of deconstructing and flat-packing their product, allowing sofas to be shipped via regular carriers, both more cheaply and more quickly.

“It’s almost like these are the 501 of furniture.” The neutral or muted colors, unadorned wooden legs, and simple shapes have become the baseline for sofas.

Source: Why Are (Most) Sofas So Bad?