It is easier and cheaper to grow and utilize. Hand processed flax is usually of much better quality than machine processed. Basically, flax and linen have become too expensive for common use in most parts of the world. Retting flax also causes tremendous pollution problems and it is seldom done today in western Europe. Both Belgium and Ireland import most of their flax from Poland and the former Soviet Union.
China is another major producer.
The plant has mostly been grown as a fiber and has been grown since prehistoric times. B.C. The fibers are extracted by retting, scutching, and pounding. Typically it is used for cordage, rope, canvas, and sailcloth. Jeans were originally made from hemp cloth. Most hemp fiber today comes from the USSR and India.