I believe part of the problem is that it's difficult to draw the line defining what an "additive" is.
Any sort of spices, ferment, baking powder, food coloring (even traditional coloring like beet juice or squid ink) could be considered additive. A lot of these things have been traditionally used for centuries. And otoh just because something has been used traditionally does guarantee its safety.
But guilty until proven innocent is what being suggested here, so you would need to check thousands of different compounds in say coffee and run trials on them all
individually?
The burden of proof would be in the company that wants to sell it. So “you” wouldn’t have to (nor your tax dollars). The company who’s investing resources to bring the product to market would have to. (And it should go without saying that they should also have to fund an impartial third party in order to do that)
Any sort of spices, ferment, baking powder, food coloring (even traditional coloring like beet juice or squid ink) could be considered additive. A lot of these things have been traditionally used for centuries. And otoh just because something has been used traditionally does guarantee its safety.