If hemp production is becoming less, it's because Government and big business are opposing it, usually by law, not because hemp is impractical as a product.
If hemp cultivation is actually profitable, then why can't the big businesses get involved? After all, they are after profits only. What about hemp cultivation on an industrial scale?
This is only a glimpse of the history lesson...
On the eve of World War II the German chemical complex of I.G. Farben was the largest chemical manufacturing enterprise in the world, with extraordinary political and economic power and influence within the Hitlerian Nazi state. I. G. has been aptly described as "a state within a state."
Research I.G. Farben. You will find that when America bombed Frankfurt at the end of WW2, the I.G. Farben buildings were spared. The excuse was that we needed a place to set up "office" for the dividing of conquered Germany. My uncle was in what would become the CIA, and he confirmed this to me, personally, even though there were things he could not talk about because of Government secrecy.
There were I.G. Farben trials. But the chemical monstrosity that Farben was, was adapted to and adopted into the American Government. Farben moved to America. This happened well before the end of the war, as shown by the Farben buildings being selected to not be bombed. The pharmaceutical houses of today are the descendants of I.G. Farben.
That is the excuse for the war on marijuana and cocaine. Both of these drugs, if properly administered, essentially destroy all disease. There would be no way for Big Pharma to make money off the populace if the people were not sick. Big Pharma essentially moved from Germany to America in WW2. But that isn't all.
Hemp was an important crop from Colonial times through World War II, when it was last widely planted across the country for the war effort.
More than 120,000 pounds of hemp fiber was needed to rig the 44-gun USS Constitution, America’s oldest Navy ship affectionately called “Old Ironsides.”
Nylon is a generic designation for a family of synthetic polymers, more specifically aliphatic or semi-aromatic polyamides. They can be melt-processed into fibers, films or shapes. The first example of nylon (nylon 6,6) was produced on February 28, 1935, by Wallace Carothers at DuPont's research facility at the DuPont Experimental Station.
In other words, aside from Big Pharma, the oil industry emerged as a going thing, replacing all kinds of products - including articles of clothing - with various plastics. The removal of hemp from the market helped insure that the oil industry would grow to gigantic size.
I'm sure that if you research it with your thinking cap on, you will be able to find all kinds of other reasons for the suppression of hemp.