There isn't a single mindset about this stuff in the US, or in France I assume. I'm American and I'm bewildered as to how people can be significantly overweight, much less obese.

I would note that many/most obese people have tried and failed to reduce their weight (or temporarily succeeded). So it's definitely seen as a highly negative trait.

There is a "body positivity" movement here that discourages people from feeling shame about their appearance. Some people see this as a negative thing, with potential health ramifications.

I'd also say that obesity in the US varies quite a bit based on geography and income bracket.

There is a small number of people who would argue any size is fine, and there are a couple of TV shows and spokespeople saying this, but it is a tiny portion of people and media representation. The dominant "real talk" is that we're too fat and that too fat is unhealthy. The dominant, unspoken attitude (as would be the case in France, it seems) is one of active discrimination and lack of mere acceptance of the humanity of obese people.

I just came back to San Francisco from a week in Paris. The biggest surprise to me was how large the typical portion of food was at a restaurant. Everywhere from a tourist oriented charcuterie to a hipster joint in Montmartre. I told my friend they looked like American sized portions.

Meanwhile the Bay Area never seemed all that obese to me. Leave the Bay Area and all of a sudden you'll see a surprising number of people so fat they can only move around in a motorized wheelchair.