I do agree that the "rising tide raises all boats" rhetoric is largely bunk. But I don't think that this one particular measure, taken at an anomalous time, is sound footing for a counterargument.
That’s mostly due to obesity, which is a consequence of the quantity and (flavor) quality of food getting better over time; a side effect of economic prosperity.
Obesity is a side effect of having so much food that calories are cheap and plentiful. That’s why obesity rates are rising everywhere in the first world. It’s also something virtually unprecedented in human history.
That decline is an anomaly. The majority of it is attributable to covid, and a significant minority attributable to fentanyl: https://www.cdc.gov/nchs/pressroom/nchs_press_releases/2022/...
I do agree that the "rising tide raises all boats" rhetoric is largely bunk. But I don't think that this one particular measure, taken at an anomalous time, is sound footing for a counterargument.