> The data from this study doesn't support your statement.

I think you're wrong.

> The increased energy intake during the ultra-processed diet resulted from consuming greater quantities of carbohydrate (280 ± 54 kcal/day; p < 0.0001) and fat (230 ± 53 kcal/day; p = 0.0004), but not protein (
2 ± 12 kcal/day; p = 0.85) (Figure 2B). The remarkable stability of absolute protein intake between the diets, along with the slight reduction in overall protein provided in the ultra-processed versus the unprocessed diet (14% versus 15.6% of calories, respectively) (Table 1), suggests that the protein leverage hypothesis could partially explain the increase in energy intake with the ultra-processed diet in an attempt to maintain a constant protein intake (Martı´nez Steele et al., 2018; Simpson and Raubenheimer, 2005).

https://www.cell.com/cell-metabolism/pdf/S1550-4131(19)30248...

Yes, they matched the meals, but the meals weren't made of homogenous goo. Participants could eat as much as they wanted of the parts they wanted.

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.