By far, the main reason for it being Outlawed is the Nutrient value it possesses in Replenishing the Soil after Starch rich crops are grown.
Since it being Outlawed in 1933…the Nutrient Value of the soil in the U.S. and Worldwide has declined to the point of 20% of its Value before 1933.
All other outlaw reasons are superseded by this fact.
The other Arguments are used to obscure their True intent for Stifling its Growth…
Ask any Farmer who knows.