Not really true. From WIKI (your recommendation !):
Plattenbau (plural: Plattenbauten, German: Platte + Bau, lit. 'panel/slab' + 'building/ construction') is a building constructed of large, prefabricated concrete slabs. The word is a compound of Platte (in this context: panel) and Bau (building).
Although Plattenbauten are often considered to be typical of East Germany, the prefabricated construction method was used extensively in West Germany and elsewhere, particularly in public housing (see tower block). In English the building method is also called large panel system-building or LPS. Prefabrication was pioneered in the Netherlands following World War I, based on construction methods developed in the United States. The first German use of plattenbau construction is what is now known as the Splanemann-Siedlung in Berlin's Lichtenberg district, constructed in 1926–1930