You're a little quick to correlate screens and health metrics. I don't think that explanation holds up at all if you consider data in other countries.
In France ("the land of delicate and healthy food", as it is sold to you), obesity rate was multiplied by 3 since the 80s. Overweight rate raised by 50%.
Diabetes has also been on the raise: double or tripled since the 90s.
You know, in general all the crap that develops in the USA reaches other countries after a while. Depending on which specific 'crap', it is just a matter of variables delays and variable intensity, but it surely comes one day.
Is it? I would associate that description more with Italy. With France I associate butter, cream, cheese, fatty cuts of meat ...
"Gourmet", "Chef", "Cuisine" and dozens of other terms: even in the English culinary vocabulary, the French words have a predominant role. It ruled the world of 'proper' cooking at some point. But I was more thinking about how, from the USA, the French are presented as having a balanced diet, eating a bit of everything but not eating too much of anything, cooking by themselves and not resorting to mostly ready, industrial, over-processed meals, how they would be a sort model in those matters related to food.
What was very fashionable at some point in the discourse on healthy food (10-15 years ago, maybe), was the Greek/Cretan diet; which was often extended to the whole Mediterranean, including Italy indeed, and south of France. Traditionally the butter & cream you mentioned are associated with northern France: the South was supposed to be a land of oil (olive oil in the most Mediterranean part, other oils in other parts) and the North a land of butter.
Said that, obesity is largely a problem of the Anglo-sphere, it has many causes, including a severe lack of food culture (eg adults who think it’s proper to eat candy bars or to eat at McDonald’s). It is not inevitable that the horrid American food habits will become the norm everywhere, the US is not the teleos history is moving towards.
https://www.sciencedirect.com/science/article/pii/S235282731...
In Japan the same trend appears but it's delayed by two decades:
https://www.sciencedirect.com/science/article/pii/S1728869X1...
Obesity and diabetes have also trended upwards outside North America but this has been mitigated by better regulation of the food industry.