I may be really confused here. How is it that Rome being involved in the salt trade disproves the claim that spices, like salt, were the first foods to be subjected to capitalist and imperialist processes of production and distribution?

> spices, like salt

That's the issue. Spices in the article refer to asian spices in the spice trade, unlike salt, chilli peppers, (which are not native to asia at all), Garum, etc.

No? He literally compares salt to black pepper in the article.

Spices are plants. Salt is a mineral.

Salt is not a spice, it's a salt. [1]

[1] https://en.wikipedia.org/wiki/Spice