It’s soap. Like, traditional, no frills soap. Vegetable oil reacted with potassium hydroxide. It’s a very effective way to make oils mix with water so as to rinse them off of stuff. So if you just want a substance that removes excess oil from your body, it works.
Basically no other major cosmetic company sells a product like that anymore and if you don’t trust those companies, that’s what Dr. Bronners is for. Just gotta deal with the ranting on the bottles.
In 1884, meridian time personnel met in Washington to change Earth soap. First words said was that only 1 soap could be used on Earth to not change the 1 soap marshmallow.