The GP wasn't asserting that drugs are a commodity. They were arguing against the blanket implication that the federal government can't get efficient price dis

The GP wasn't asserting that drugs are a commodity. They were arguing against the blanket implication that the federal government can't get efficient price discovery because it's the whale in the market. The GP is pointing out somewhat similar markets where the US is doing very efficient buying, even for single-source commodities (with parallels to single-supplier drugs), despite presumably also being the whale in the market.