Yes, exactly: there were plenty of carbs available to both groups, but those with the highly processed variety ate more of those carbs than those without, suggesting that it's not the availability of the carbs but rather the degree of processing that makes the person eat more of what's available.
Though I would agree that this evidence leaves the possibility that carbs in general are less sating, but that highly processed carbs are even worse, and so the degree of processing would still be linked to weight gain.
It's not clear if that's because there's some sort of stomach-brain "signal" that's getting confused, or because highly processed foods are designed to taste maximally good versus less processed and so people eat more.
Though I would agree that this evidence leaves the possibility that carbs in general are less sating, but that highly processed carbs are even worse, and so the degree of processing would still be linked to weight gain.
It's not clear if that's because there's some sort of stomach-brain "signal" that's getting confused, or because highly processed foods are designed to taste maximally good versus less processed and so people eat more.