Complex sentence: Many of these producers have gone out of businesses over the past few decades, succumbing to the Quartz Revolution, as they were unable to compete with the inexpensive electronic movements produced by Asian manufacturers, which flooded the market during the 1960s and 1970s.
Split into simpler sentences: Many of these producers have gone out of businesses over the past few decades, succumbing to the Quartz Revolution. Most were unable to compete with the inexpensive electronic movements produced by Asian manufacturers, which flooded the market during the 1960s and 1970s.