[gusgus01]

Even that article carries on about the experience of having the coffee hot, eg

"This doesn’t mean drinking room-temperature coffee exclusively. The complete experience encompasses the entire temperature journey." and "High temperatures deliver immediate aromatic impact—the unique, irreplaceable value of fresh coffee."

I'm also not sure bitterness should be considered a defect in coffee, it's part of the flavor profile and actually peaks in perception at a higher temperature according to that article.