You charge producers FIFTY PERCENT to create content for your website? This is what is wrong with the 'Gig Economy' - you charge too damn much with out providing value yourself or to the sellers.
What do you provide for the 50% you are charging? It sure is not web design or marketing - I looked at your website and it looks like you just bought it from ThemeForest.
Not even Google/Apple take such a large cut and they catually provide more value to their value-creators and they also don't try to sell themselves as altruistic